diff --git a/vendor/github.com/jessevdk/go-flags/.travis.yml b/vendor/github.com/jessevdk/go-flags/.travis.yml
new file mode 100644
index 0000000..0f0728d
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/.travis.yml
@@ -0,0 +1,44 @@
+language: go
+
+os:
+  - linux
+  - osx
+
+go:
+  - 1.x
+  - 1.7.x
+  - 1.8.x
+  - 1.9.x
+  - 1.10.x
+
+install:
+  # go-flags
+  - go get -d -v ./...
+  - go build -v ./...
+
+  # linting
+  - go get github.com/golang/lint/golint
+
+  # code coverage
+  - go get golang.org/x/tools/cmd/cover
+  - go get github.com/onsi/ginkgo/ginkgo
+  - go get github.com/modocache/gover
+  - if [ "$TRAVIS_SECURE_ENV_VARS" = "true" ]; then go get github.com/mattn/goveralls; fi
+
+script:
+  # go-flags
+  - $(exit $(gofmt -l . | wc -l))
+  - go test -v ./...
+
+  # linting
+  - go tool vet -all=true -v=true . || true
+  - $(go env GOPATH | awk 'BEGIN{FS=":"} {print $1}')/bin/golint ./...
+
+  # code coverage
+  - $(go env GOPATH | awk 'BEGIN{FS=":"} {print $1}')/bin/ginkgo -r -cover
+  - $(go env GOPATH | awk 'BEGIN{FS=":"} {print $1}')/bin/gover
+  - if [ "$TRAVIS_SECURE_ENV_VARS" = "true" ]; then $(go env GOPATH | awk 'BEGIN{FS=":"} {print $1}')/bin/goveralls -coverprofile=gover.coverprofile -service=travis-ci -repotoken $COVERALLS_TOKEN; fi
+
+env:
+  # coveralls.io
+  secure: "RCYbiB4P0RjQRIoUx/vG/AjP3mmYCbzOmr86DCww1Z88yNcy3hYr3Cq8rpPtYU5v0g7wTpu4adaKIcqRE9xknYGbqj3YWZiCoBP1/n4Z+9sHW3Dsd9D/GRGeHUus0laJUGARjWoCTvoEtOgTdGQDoX7mH+pUUY0FBltNYUdOiiU="
diff --git a/vendor/github.com/jessevdk/go-flags/LICENSE b/vendor/github.com/jessevdk/go-flags/LICENSE
new file mode 100644
index 0000000..bcca0d5
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/LICENSE
@@ -0,0 +1,26 @@
+Copyright (c) 2012 Jesse van den Kieboom. All rights reserved.
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+     notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+     copyright notice, this list of conditions and the following disclaimer
+     in the documentation and/or other materials provided with the
+     distribution.
+   * Neither the name of Google Inc. nor the names of its
+     contributors may be used to endorse or promote products derived from
+     this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/github.com/jessevdk/go-flags/README.md b/vendor/github.com/jessevdk/go-flags/README.md
new file mode 100644
index 0000000..3b02394
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/README.md
@@ -0,0 +1,134 @@
+go-flags: a go library for parsing command line arguments
+=========================================================
+
+[![GoDoc](https://godoc.org/github.com/jessevdk/go-flags?status.png)](https://godoc.org/github.com/jessevdk/go-flags) [![Build Status](https://travis-ci.org/jessevdk/go-flags.svg?branch=master)](https://travis-ci.org/jessevdk/go-flags) [![Coverage Status](https://img.shields.io/coveralls/jessevdk/go-flags.svg)](https://coveralls.io/r/jessevdk/go-flags?branch=master)
+
+This library provides similar functionality to the builtin flag library of
+go, but provides much more functionality and nicer formatting. From the
+documentation:
+
+Package flags provides an extensive command line option parser.
+The flags package is similar in functionality to the go builtin flag package
+but provides more options and uses reflection to provide a convenient and
+succinct way of specifying command line options.
+
+Supported features:
+* Options with short names (-v)
+* Options with long names (--verbose)
+* Options with and without arguments (bool v.s. other type)
+* Options with optional arguments and default values
+* Multiple option groups each containing a set of options
+* Generate and print well-formatted help message
+* Passing remaining command line arguments after -- (optional)
+* Ignoring unknown command line options (optional)
+* Supports -I/usr/include -I=/usr/include -I /usr/include option argument specification
+* Supports multiple short options -aux
+* Supports all primitive go types (string, int{8..64}, uint{8..64}, float)
+* Supports same option multiple times (can store in slice or last option counts)
+* Supports maps
+* Supports function callbacks
+* Supports namespaces for (nested) option groups
+
+The flags package uses structs, reflection and struct field tags
+to allow users to specify command line options. This results in very simple
+and concise specification of your application options. For example:
+
+```go
+type Options struct {
+	Verbose []bool `short:"v" long:"verbose" description:"Show verbose debug information"`
+}
+```
+
+This specifies one option with a short name -v and a long name --verbose.
+When either -v or --verbose is found on the command line, a 'true' value
+will be appended to the Verbose field. e.g. when specifying -vvv, the
+resulting value of Verbose will be {[true, true, true]}.
+
+Example:
+--------
+```go
+var opts struct {
+	// Slice of bool will append 'true' each time the option
+	// is encountered (can be set multiple times, like -vvv)
+	Verbose []bool `short:"v" long:"verbose" description:"Show verbose debug information"`
+
+	// Example of automatic marshalling to desired type (uint)
+	Offset uint `long:"offset" description:"Offset"`
+
+	// Example of a callback, called each time the option is found.
+	Call func(string) `short:"c" description:"Call phone number"`
+
+	// Example of a required flag
+	Name string `short:"n" long:"name" description:"A name" required:"true"`
+
+	// Example of a value name
+	File string `short:"f" long:"file" description:"A file" value-name:"FILE"`
+
+	// Example of a pointer
+	Ptr *int `short:"p" description:"A pointer to an integer"`
+
+	// Example of a slice of strings
+	StringSlice []string `short:"s" description:"A slice of strings"`
+
+	// Example of a slice of pointers
+	PtrSlice []*string `long:"ptrslice" description:"A slice of pointers to string"`
+
+	// Example of a map
+	IntMap map[string]int `long:"intmap" description:"A map from string to int"`
+}
+
+// Callback which will invoke callto:<argument> to call a number.
+// Note that this works just on OS X (and probably only with
+// Skype) but it shows the idea.
+opts.Call = func(num string) {
+	cmd := exec.Command("open", "callto:"+num)
+	cmd.Start()
+	cmd.Process.Release()
+}
+
+// Make some fake arguments to parse.
+args := []string{
+	"-vv",
+	"--offset=5",
+	"-n", "Me",
+	"-p", "3",
+	"-s", "hello",
+	"-s", "world",
+	"--ptrslice", "hello",
+	"--ptrslice", "world",
+	"--intmap", "a:1",
+	"--intmap", "b:5",
+	"arg1",
+	"arg2",
+	"arg3",
+}
+
+// Parse flags from `args'. Note that here we use flags.ParseArgs for
+// the sake of making a working example. Normally, you would simply use
+// flags.Parse(&opts) which uses os.Args
+args, err := flags.ParseArgs(&opts, args)
+
+if err != nil {
+	panic(err)
+}
+
+fmt.Printf("Verbosity: %v\n", opts.Verbose)
+fmt.Printf("Offset: %d\n", opts.Offset)
+fmt.Printf("Name: %s\n", opts.Name)
+fmt.Printf("Ptr: %d\n", *opts.Ptr)
+fmt.Printf("StringSlice: %v\n", opts.StringSlice)
+fmt.Printf("PtrSlice: [%v %v]\n", *opts.PtrSlice[0], *opts.PtrSlice[1])
+fmt.Printf("IntMap: [a:%v b:%v]\n", opts.IntMap["a"], opts.IntMap["b"])
+fmt.Printf("Remaining args: %s\n", strings.Join(args, " "))
+
+// Output: Verbosity: [true true]
+// Offset: 5
+// Name: Me
+// Ptr: 3
+// StringSlice: [hello world]
+// PtrSlice: [hello world]
+// IntMap: [a:1 b:5]
+// Remaining args: arg1 arg2 arg3
+```
+
+More information can be found in the godocs: <http://godoc.org/github.com/jessevdk/go-flags>
diff --git a/vendor/github.com/jessevdk/go-flags/arg.go b/vendor/github.com/jessevdk/go-flags/arg.go
new file mode 100644
index 0000000..8ec6204
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/arg.go
@@ -0,0 +1,27 @@
+package flags
+
+import (
+	"reflect"
+)
+
+// Arg represents a positional argument on the command line.
+type Arg struct {
+	// The name of the positional argument (used in the help)
+	Name string
+
+	// A description of the positional argument (used in the help)
+	Description string
+
+	// The minimal number of required positional arguments
+	Required int
+
+	// The maximum number of required positional arguments
+	RequiredMaximum int
+
+	value reflect.Value
+	tag   multiTag
+}
+
+func (a *Arg) isRemaining() bool {
+	return a.value.Type().Kind() == reflect.Slice
+}
diff --git a/vendor/github.com/jessevdk/go-flags/check_crosscompile.sh b/vendor/github.com/jessevdk/go-flags/check_crosscompile.sh
new file mode 100644
index 0000000..c494f61
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/check_crosscompile.sh
@@ -0,0 +1,16 @@
+#!/bin/bash
+
+set -e
+
+echo '# linux arm7'
+GOARM=7 GOARCH=arm GOOS=linux go build
+echo '# linux arm5'
+GOARM=5 GOARCH=arm GOOS=linux go build
+echo '# windows 386'
+GOARCH=386 GOOS=windows go build
+echo '# windows amd64'
+GOARCH=amd64 GOOS=windows go build
+echo '# darwin'
+GOARCH=amd64 GOOS=darwin go build
+echo '# freebsd'
+GOARCH=amd64 GOOS=freebsd go build
diff --git a/vendor/github.com/jessevdk/go-flags/closest.go b/vendor/github.com/jessevdk/go-flags/closest.go
new file mode 100644
index 0000000..3b51875
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/closest.go
@@ -0,0 +1,59 @@
+package flags
+
+func levenshtein(s string, t string) int {
+	if len(s) == 0 {
+		return len(t)
+	}
+
+	if len(t) == 0 {
+		return len(s)
+	}
+
+	dists := make([][]int, len(s)+1)
+	for i := range dists {
+		dists[i] = make([]int, len(t)+1)
+		dists[i][0] = i
+	}
+
+	for j := range t {
+		dists[0][j] = j
+	}
+
+	for i, sc := range s {
+		for j, tc := range t {
+			if sc == tc {
+				dists[i+1][j+1] = dists[i][j]
+			} else {
+				dists[i+1][j+1] = dists[i][j] + 1
+				if dists[i+1][j] < dists[i+1][j+1] {
+					dists[i+1][j+1] = dists[i+1][j] + 1
+				}
+				if dists[i][j+1] < dists[i+1][j+1] {
+					dists[i+1][j+1] = dists[i][j+1] + 1
+				}
+			}
+		}
+	}
+
+	return dists[len(s)][len(t)]
+}
+
+func closestChoice(cmd string, choices []string) (string, int) {
+	if len(choices) == 0 {
+		return "", 0
+	}
+
+	mincmd := -1
+	mindist := -1
+
+	for i, c := range choices {
+		l := levenshtein(cmd, c)
+
+		if mincmd < 0 || l < mindist {
+			mindist = l
+			mincmd = i
+		}
+	}
+
+	return choices[mincmd], mindist
+}
diff --git a/vendor/github.com/jessevdk/go-flags/command.go b/vendor/github.com/jessevdk/go-flags/command.go
new file mode 100644
index 0000000..486bacb
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/command.go
@@ -0,0 +1,465 @@
+package flags
+
+import (
+	"reflect"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+// Command represents an application command. Commands can be added to the
+// parser (which itself is a command) and are selected/executed when its name
+// is specified on the command line. The Command type embeds a Group and
+// therefore also carries a set of command specific options.
+type Command struct {
+	// Embedded, see Group for more information
+	*Group
+
+	// The name by which the command can be invoked
+	Name string
+
+	// The active sub command (set by parsing) or nil
+	Active *Command
+
+	// Whether subcommands are optional
+	SubcommandsOptional bool
+
+	// Aliases for the command
+	Aliases []string
+
+	// Whether positional arguments are required
+	ArgsRequired bool
+
+	commands            []*Command
+	hasBuiltinHelpGroup bool
+	args                []*Arg
+}
+
+// Commander is an interface which can be implemented by any command added in
+// the options. When implemented, the Execute method will be called for the last
+// specified (sub)command providing the remaining command line arguments.
+type Commander interface {
+	// Execute will be called for the last active (sub)command. The
+	// args argument contains the remaining command line arguments. The
+	// error that Execute returns will be eventually passed out of the
+	// Parse method of the Parser.
+	Execute(args []string) error
+}
+
+// Usage is an interface which can be implemented to show a custom usage string
+// in the help message shown for a command.
+type Usage interface {
+	// Usage is called for commands to allow customized printing of command
+	// usage in the generated help message.
+	Usage() string
+}
+
+type lookup struct {
+	shortNames map[string]*Option
+	longNames  map[string]*Option
+
+	commands map[string]*Command
+}
+
+// AddCommand adds a new command to the parser with the given name and data. The
+// data needs to be a pointer to a struct from which the fields indicate which
+// options are in the command. The provided data can implement the Command and
+// Usage interfaces.
+func (c *Command) AddCommand(command string, shortDescription string, longDescription string, data interface{}) (*Command, error) {
+	cmd := newCommand(command, shortDescription, longDescription, data)
+
+	cmd.parent = c
+
+	if err := cmd.scan(); err != nil {
+		return nil, err
+	}
+
+	c.commands = append(c.commands, cmd)
+	return cmd, nil
+}
+
+// AddGroup adds a new group to the command with the given name and data. The
+// data needs to be a pointer to a struct from which the fields indicate which
+// options are in the group.
+func (c *Command) AddGroup(shortDescription string, longDescription string, data interface{}) (*Group, error) {
+	group := newGroup(shortDescription, longDescription, data)
+
+	group.parent = c
+
+	if err := group.scanType(c.scanSubcommandHandler(group)); err != nil {
+		return nil, err
+	}
+
+	c.groups = append(c.groups, group)
+	return group, nil
+}
+
+// Commands returns a list of subcommands of this command.
+func (c *Command) Commands() []*Command {
+	return c.commands
+}
+
+// Find locates the subcommand with the given name and returns it. If no such
+// command can be found Find will return nil.
+func (c *Command) Find(name string) *Command {
+	for _, cc := range c.commands {
+		if cc.match(name) {
+			return cc
+		}
+	}
+
+	return nil
+}
+
+// FindOptionByLongName finds an option that is part of the command, or any of
+// its parent commands, by matching its long name (including the option
+// namespace).
+func (c *Command) FindOptionByLongName(longName string) (option *Option) {
+	for option == nil && c != nil {
+		option = c.Group.FindOptionByLongName(longName)
+
+		c, _ = c.parent.(*Command)
+	}
+
+	return option
+}
+
+// FindOptionByShortName finds an option that is part of the command, or any of
+// its parent commands, by matching its long name (including the option
+// namespace).
+func (c *Command) FindOptionByShortName(shortName rune) (option *Option) {
+	for option == nil && c != nil {
+		option = c.Group.FindOptionByShortName(shortName)
+
+		c, _ = c.parent.(*Command)
+	}
+
+	return option
+}
+
+// Args returns a list of positional arguments associated with this command.
+func (c *Command) Args() []*Arg {
+	ret := make([]*Arg, len(c.args))
+	copy(ret, c.args)
+
+	return ret
+}
+
+func newCommand(name string, shortDescription string, longDescription string, data interface{}) *Command {
+	return &Command{
+		Group: newGroup(shortDescription, longDescription, data),
+		Name:  name,
+	}
+}
+
+func (c *Command) scanSubcommandHandler(parentg *Group) scanHandler {
+	f := func(realval reflect.Value, sfield *reflect.StructField) (bool, error) {
+		mtag := newMultiTag(string(sfield.Tag))
+
+		if err := mtag.Parse(); err != nil {
+			return true, err
+		}
+
+		positional := mtag.Get("positional-args")
+
+		if len(positional) != 0 {
+			stype := realval.Type()
+
+			for i := 0; i < stype.NumField(); i++ {
+				field := stype.Field(i)
+
+				m := newMultiTag((string(field.Tag)))
+
+				if err := m.Parse(); err != nil {
+					return true, err
+				}
+
+				name := m.Get("positional-arg-name")
+
+				if len(name) == 0 {
+					name = field.Name
+				}
+
+				required := -1
+				requiredMaximum := -1
+
+				sreq := m.Get("required")
+
+				if sreq != "" {
+					required = 1
+
+					rng := strings.SplitN(sreq, "-", 2)
+
+					if len(rng) > 1 {
+						if preq, err := strconv.ParseInt(rng[0], 10, 32); err == nil {
+							required = int(preq)
+						}
+
+						if preq, err := strconv.ParseInt(rng[1], 10, 32); err == nil {
+							requiredMaximum = int(preq)
+						}
+					} else {
+						if preq, err := strconv.ParseInt(sreq, 10, 32); err == nil {
+							required = int(preq)
+						}
+					}
+				}
+
+				arg := &Arg{
+					Name:            name,
+					Description:     m.Get("description"),
+					Required:        required,
+					RequiredMaximum: requiredMaximum,
+
+					value: realval.Field(i),
+					tag:   m,
+				}
+
+				c.args = append(c.args, arg)
+
+				if len(mtag.Get("required")) != 0 {
+					c.ArgsRequired = true
+				}
+			}
+
+			return true, nil
+		}
+
+		subcommand := mtag.Get("command")
+
+		if len(subcommand) != 0 {
+			var ptrval reflect.Value
+
+			if realval.Kind() == reflect.Ptr {
+				ptrval = realval
+
+				if ptrval.IsNil() {
+					ptrval.Set(reflect.New(ptrval.Type().Elem()))
+				}
+			} else {
+				ptrval = realval.Addr()
+			}
+
+			shortDescription := mtag.Get("description")
+			longDescription := mtag.Get("long-description")
+			subcommandsOptional := mtag.Get("subcommands-optional")
+			aliases := mtag.GetMany("alias")
+
+			subc, err := c.AddCommand(subcommand, shortDescription, longDescription, ptrval.Interface())
+
+			if err != nil {
+				return true, err
+			}
+
+			subc.Hidden = mtag.Get("hidden") != ""
+
+			if len(subcommandsOptional) > 0 {
+				subc.SubcommandsOptional = true
+			}
+
+			if len(aliases) > 0 {
+				subc.Aliases = aliases
+			}
+
+			return true, nil
+		}
+
+		return parentg.scanSubGroupHandler(realval, sfield)
+	}
+
+	return f
+}
+
+func (c *Command) scan() error {
+	return c.scanType(c.scanSubcommandHandler(c.Group))
+}
+
+func (c *Command) eachOption(f func(*Command, *Group, *Option)) {
+	c.eachCommand(func(c *Command) {
+		c.eachGroup(func(g *Group) {
+			for _, option := range g.options {
+				f(c, g, option)
+			}
+		})
+	}, true)
+}
+
+func (c *Command) eachCommand(f func(*Command), recurse bool) {
+	f(c)
+
+	for _, cc := range c.commands {
+		if recurse {
+			cc.eachCommand(f, true)
+		} else {
+			f(cc)
+		}
+	}
+}
+
+func (c *Command) eachActiveGroup(f func(cc *Command, g *Group)) {
+	c.eachGroup(func(g *Group) {
+		f(c, g)
+	})
+
+	if c.Active != nil {
+		c.Active.eachActiveGroup(f)
+	}
+}
+
+func (c *Command) addHelpGroups(showHelp func() error) {
+	if !c.hasBuiltinHelpGroup {
+		c.addHelpGroup(showHelp)
+		c.hasBuiltinHelpGroup = true
+	}
+
+	for _, cc := range c.commands {
+		cc.addHelpGroups(showHelp)
+	}
+}
+
+func (c *Command) makeLookup() lookup {
+	ret := lookup{
+		shortNames: make(map[string]*Option),
+		longNames:  make(map[string]*Option),
+		commands:   make(map[string]*Command),
+	}
+
+	parent := c.parent
+
+	var parents []*Command
+
+	for parent != nil {
+		if cmd, ok := parent.(*Command); ok {
+			parents = append(parents, cmd)
+			parent = cmd.parent
+		} else {
+			parent = nil
+		}
+	}
+
+	for i := len(parents) - 1; i >= 0; i-- {
+		parents[i].fillLookup(&ret, true)
+	}
+
+	c.fillLookup(&ret, false)
+	return ret
+}
+
+func (c *Command) fillLookup(ret *lookup, onlyOptions bool) {
+	c.eachGroup(func(g *Group) {
+		for _, option := range g.options {
+			if option.ShortName != 0 {
+				ret.shortNames[string(option.ShortName)] = option
+			}
+
+			if len(option.LongName) > 0 {
+				ret.longNames[option.LongNameWithNamespace()] = option
+			}
+		}
+	})
+
+	if onlyOptions {
+		return
+	}
+
+	for _, subcommand := range c.commands {
+		ret.commands[subcommand.Name] = subcommand
+
+		for _, a := range subcommand.Aliases {
+			ret.commands[a] = subcommand
+		}
+	}
+}
+
+func (c *Command) groupByName(name string) *Group {
+	if grp := c.Group.groupByName(name); grp != nil {
+		return grp
+	}
+
+	for _, subc := range c.commands {
+		prefix := subc.Name + "."
+
+		if strings.HasPrefix(name, prefix) {
+			if grp := subc.groupByName(name[len(prefix):]); grp != nil {
+				return grp
+			}
+		} else if name == subc.Name {
+			return subc.Group
+		}
+	}
+
+	return nil
+}
+
+type commandList []*Command
+
+func (c commandList) Less(i, j int) bool {
+	return c[i].Name < c[j].Name
+}
+
+func (c commandList) Len() int {
+	return len(c)
+}
+
+func (c commandList) Swap(i, j int) {
+	c[i], c[j] = c[j], c[i]
+}
+
+func (c *Command) sortedVisibleCommands() []*Command {
+	ret := commandList(c.visibleCommands())
+	sort.Sort(ret)
+
+	return []*Command(ret)
+}
+
+func (c *Command) visibleCommands() []*Command {
+	ret := make([]*Command, 0, len(c.commands))
+
+	for _, cmd := range c.commands {
+		if !cmd.Hidden {
+			ret = append(ret, cmd)
+		}
+	}
+
+	return ret
+}
+
+func (c *Command) match(name string) bool {
+	if c.Name == name {
+		return true
+	}
+
+	for _, v := range c.Aliases {
+		if v == name {
+			return true
+		}
+	}
+
+	return false
+}
+
+func (c *Command) hasCliOptions() bool {
+	ret := false
+
+	c.eachGroup(func(g *Group) {
+		if g.isBuiltinHelp {
+			return
+		}
+
+		for _, opt := range g.options {
+			if opt.canCli() {
+				ret = true
+			}
+		}
+	})
+
+	return ret
+}
+
+func (c *Command) fillParseState(s *parseState) {
+	s.positional = make([]*Arg, len(c.args))
+	copy(s.positional, c.args)
+
+	s.lookup = c.makeLookup()
+	s.command = c
+}
diff --git a/vendor/github.com/jessevdk/go-flags/completion.go b/vendor/github.com/jessevdk/go-flags/completion.go
new file mode 100644
index 0000000..7a7a08b
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/completion.go
@@ -0,0 +1,309 @@
+package flags
+
+import (
+	"fmt"
+	"path/filepath"
+	"reflect"
+	"sort"
+	"strings"
+	"unicode/utf8"
+)
+
+// Completion is a type containing information of a completion.
+type Completion struct {
+	// The completed item
+	Item string
+
+	// A description of the completed item (optional)
+	Description string
+}
+
+type completions []Completion
+
+func (c completions) Len() int {
+	return len(c)
+}
+
+func (c completions) Less(i, j int) bool {
+	return c[i].Item < c[j].Item
+}
+
+func (c completions) Swap(i, j int) {
+	c[i], c[j] = c[j], c[i]
+}
+
+// Completer is an interface which can be implemented by types
+// to provide custom command line argument completion.
+type Completer interface {
+	// Complete receives a prefix representing a (partial) value
+	// for its type and should provide a list of possible valid
+	// completions.
+	Complete(match string) []Completion
+}
+
+type completion struct {
+	parser *Parser
+}
+
+// Filename is a string alias which provides filename completion.
+type Filename string
+
+func completionsWithoutDescriptions(items []string) []Completion {
+	ret := make([]Completion, len(items))
+
+	for i, v := range items {
+		ret[i].Item = v
+	}
+
+	return ret
+}
+
+// Complete returns a list of existing files with the given
+// prefix.
+func (f *Filename) Complete(match string) []Completion {
+	ret, _ := filepath.Glob(match + "*")
+	return completionsWithoutDescriptions(ret)
+}
+
+func (c *completion) skipPositional(s *parseState, n int) {
+	if n >= len(s.positional) {
+		s.positional = nil
+	} else {
+		s.positional = s.positional[n:]
+	}
+}
+
+func (c *completion) completeOptionNames(s *parseState, prefix string, match string, short bool) []Completion {
+	if short && len(match) != 0 {
+		return []Completion{
+			Completion{
+				Item: prefix + match,
+			},
+		}
+	}
+
+	var results []Completion
+	repeats := map[string]bool{}
+
+	for name, opt := range s.lookup.longNames {
+		if strings.HasPrefix(name, match) && !opt.Hidden {
+			results = append(results, Completion{
+				Item:        defaultLongOptDelimiter + name,
+				Description: opt.Description,
+			})
+
+			if short {
+				repeats[string(opt.ShortName)] = true
+			}
+		}
+	}
+
+	if short {
+		for name, opt := range s.lookup.shortNames {
+			if _, exist := repeats[name]; !exist && strings.HasPrefix(name, match) && !opt.Hidden {
+				results = append(results, Completion{
+					Item:        string(defaultShortOptDelimiter) + name,
+					Description: opt.Description,
+				})
+			}
+		}
+	}
+
+	return results
+}
+
+func (c *completion) completeNamesForLongPrefix(s *parseState, prefix string, match string) []Completion {
+	return c.completeOptionNames(s, prefix, match, false)
+}
+
+func (c *completion) completeNamesForShortPrefix(s *parseState, prefix string, match string) []Completion {
+	return c.completeOptionNames(s, prefix, match, true)
+}
+
+func (c *completion) completeCommands(s *parseState, match string) []Completion {
+	n := make([]Completion, 0, len(s.command.commands))
+
+	for _, cmd := range s.command.commands {
+		if cmd.data != c && strings.HasPrefix(cmd.Name, match) {
+			n = append(n, Completion{
+				Item:        cmd.Name,
+				Description: cmd.ShortDescription,
+			})
+		}
+	}
+
+	return n
+}
+
+func (c *completion) completeValue(value reflect.Value, prefix string, match string) []Completion {
+	if value.Kind() == reflect.Slice {
+		value = reflect.New(value.Type().Elem())
+	}
+	i := value.Interface()
+
+	var ret []Completion
+
+	if cmp, ok := i.(Completer); ok {
+		ret = cmp.Complete(match)
+	} else if value.CanAddr() {
+		if cmp, ok = value.Addr().Interface().(Completer); ok {
+			ret = cmp.Complete(match)
+		}
+	}
+
+	for i, v := range ret {
+		ret[i].Item = prefix + v.Item
+	}
+
+	return ret
+}
+
+func (c *completion) complete(args []string) []Completion {
+	if len(args) == 0 {
+		args = []string{""}
+	}
+
+	s := &parseState{
+		args: args,
+	}
+
+	c.parser.fillParseState(s)
+
+	var opt *Option
+
+	for len(s.args) > 1 {
+		arg := s.pop()
+
+		if (c.parser.Options&PassDoubleDash) != None && arg == "--" {
+			opt = nil
+			c.skipPositional(s, len(s.args)-1)
+
+			break
+		}
+
+		if argumentIsOption(arg) {
+			prefix, optname, islong := stripOptionPrefix(arg)
+			optname, _, argument := splitOption(prefix, optname, islong)
+
+			if argument == nil {
+				var o *Option
+				canarg := true
+
+				if islong {
+					o = s.lookup.longNames[optname]
+				} else {
+					for i, r := range optname {
+						sname := string(r)
+						o = s.lookup.shortNames[sname]
+
+						if o == nil {
+							break
+						}
+
+						if i == 0 && o.canArgument() && len(optname) != len(sname) {
+							canarg = false
+							break
+						}
+					}
+				}
+
+				if o == nil && (c.parser.Options&PassAfterNonOption) != None {
+					opt = nil
+					c.skipPositional(s, len(s.args)-1)
+
+					break
+				} else if o != nil && o.canArgument() && !o.OptionalArgument && canarg {
+					if len(s.args) > 1 {
+						s.pop()
+					} else {
+						opt = o
+					}
+				}
+			}
+		} else {
+			if len(s.positional) > 0 {
+				if !s.positional[0].isRemaining() {
+					// Don't advance beyond a remaining positional arg (because
+					// it consumes all subsequent args).
+					s.positional = s.positional[1:]
+				}
+			} else if cmd, ok := s.lookup.commands[arg]; ok {
+				cmd.fillParseState(s)
+			}
+
+			opt = nil
+		}
+	}
+
+	lastarg := s.args[len(s.args)-1]
+	var ret []Completion
+
+	if opt != nil {
+		// Completion for the argument of 'opt'
+		ret = c.completeValue(opt.value, "", lastarg)
+	} else if argumentStartsOption(lastarg) {
+		// Complete the option
+		prefix, optname, islong := stripOptionPrefix(lastarg)
+		optname, split, argument := splitOption(prefix, optname, islong)
+
+		if argument == nil && !islong {
+			rname, n := utf8.DecodeRuneInString(optname)
+			sname := string(rname)
+
+			if opt := s.lookup.shortNames[sname]; opt != nil && opt.canArgument() {
+				ret = c.completeValue(opt.value, prefix+sname, optname[n:])
+			} else {
+				ret = c.completeNamesForShortPrefix(s, prefix, optname)
+			}
+		} else if argument != nil {
+			if islong {
+				opt = s.lookup.longNames[optname]
+			} else {
+				opt = s.lookup.shortNames[optname]
+			}
+
+			if opt != nil {
+				ret = c.completeValue(opt.value, prefix+optname+split, *argument)
+			}
+		} else if islong {
+			ret = c.completeNamesForLongPrefix(s, prefix, optname)
+		} else {
+			ret = c.completeNamesForShortPrefix(s, prefix, optname)
+		}
+	} else if len(s.positional) > 0 {
+		// Complete for positional argument
+		ret = c.completeValue(s.positional[0].value, "", lastarg)
+	} else if len(s.command.commands) > 0 {
+		// Complete for command
+		ret = c.completeCommands(s, lastarg)
+	}
+
+	sort.Sort(completions(ret))
+	return ret
+}
+
+func (c *completion) print(items []Completion, showDescriptions bool) {
+	if showDescriptions && len(items) > 1 {
+		maxl := 0
+
+		for _, v := range items {
+			if len(v.Item) > maxl {
+				maxl = len(v.Item)
+			}
+		}
+
+		for _, v := range items {
+			fmt.Printf("%s", v.Item)
+
+			if len(v.Description) > 0 {
+				fmt.Printf("%s  # %s", strings.Repeat(" ", maxl-len(v.Item)), v.Description)
+			}
+
+			fmt.Printf("\n")
+		}
+	} else {
+		for _, v := range items {
+			fmt.Println(v.Item)
+		}
+	}
+}
diff --git a/vendor/github.com/jessevdk/go-flags/convert.go b/vendor/github.com/jessevdk/go-flags/convert.go
new file mode 100644
index 0000000..984aac8
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/convert.go
@@ -0,0 +1,348 @@
+// Copyright 2012 Jesse van den Kieboom. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flags
+
+import (
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// Marshaler is the interface implemented by types that can marshal themselves
+// to a string representation of the flag.
+type Marshaler interface {
+	// MarshalFlag marshals a flag value to its string representation.
+	MarshalFlag() (string, error)
+}
+
+// Unmarshaler is the interface implemented by types that can unmarshal a flag
+// argument to themselves. The provided value is directly passed from the
+// command line.
+type Unmarshaler interface {
+	// UnmarshalFlag unmarshals a string value representation to the flag
+	// value (which therefore needs to be a pointer receiver).
+	UnmarshalFlag(value string) error
+}
+
+func getBase(options multiTag, base int) (int, error) {
+	sbase := options.Get("base")
+
+	var err error
+	var ivbase int64
+
+	if sbase != "" {
+		ivbase, err = strconv.ParseInt(sbase, 10, 32)
+		base = int(ivbase)
+	}
+
+	return base, err
+}
+
+func convertMarshal(val reflect.Value) (bool, string, error) {
+	// Check first for the Marshaler interface
+	if val.Type().NumMethod() > 0 && val.CanInterface() {
+		if marshaler, ok := val.Interface().(Marshaler); ok {
+			ret, err := marshaler.MarshalFlag()
+			return true, ret, err
+		}
+	}
+
+	return false, "", nil
+}
+
+func convertToString(val reflect.Value, options multiTag) (string, error) {
+	if ok, ret, err := convertMarshal(val); ok {
+		return ret, err
+	}
+
+	tp := val.Type()
+
+	// Support for time.Duration
+	if tp == reflect.TypeOf((*time.Duration)(nil)).Elem() {
+		stringer := val.Interface().(fmt.Stringer)
+		return stringer.String(), nil
+	}
+
+	switch tp.Kind() {
+	case reflect.String:
+		return val.String(), nil
+	case reflect.Bool:
+		if val.Bool() {
+			return "true", nil
+		}
+
+		return "false", nil
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		base, err := getBase(options, 10)
+
+		if err != nil {
+			return "", err
+		}
+
+		return strconv.FormatInt(val.Int(), base), nil
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		base, err := getBase(options, 10)
+
+		if err != nil {
+			return "", err
+		}
+
+		return strconv.FormatUint(val.Uint(), base), nil
+	case reflect.Float32, reflect.Float64:
+		return strconv.FormatFloat(val.Float(), 'g', -1, tp.Bits()), nil
+	case reflect.Slice:
+		if val.Len() == 0 {
+			return "", nil
+		}
+
+		ret := "["
+
+		for i := 0; i < val.Len(); i++ {
+			if i != 0 {
+				ret += ", "
+			}
+
+			item, err := convertToString(val.Index(i), options)
+
+			if err != nil {
+				return "", err
+			}
+
+			ret += item
+		}
+
+		return ret + "]", nil
+	case reflect.Map:
+		ret := "{"
+
+		for i, key := range val.MapKeys() {
+			if i != 0 {
+				ret += ", "
+			}
+
+			keyitem, err := convertToString(key, options)
+
+			if err != nil {
+				return "", err
+			}
+
+			item, err := convertToString(val.MapIndex(key), options)
+
+			if err != nil {
+				return "", err
+			}
+
+			ret += keyitem + ":" + item
+		}
+
+		return ret + "}", nil
+	case reflect.Ptr:
+		return convertToString(reflect.Indirect(val), options)
+	case reflect.Interface:
+		if !val.IsNil() {
+			return convertToString(val.Elem(), options)
+		}
+	}
+
+	return "", nil
+}
+
+func convertUnmarshal(val string, retval reflect.Value) (bool, error) {
+	if retval.Type().NumMethod() > 0 && retval.CanInterface() {
+		if unmarshaler, ok := retval.Interface().(Unmarshaler); ok {
+			if retval.IsNil() {
+				retval.Set(reflect.New(retval.Type().Elem()))
+
+				// Re-assign from the new value
+				unmarshaler = retval.Interface().(Unmarshaler)
+			}
+
+			return true, unmarshaler.UnmarshalFlag(val)
+		}
+	}
+
+	if retval.Type().Kind() != reflect.Ptr && retval.CanAddr() {
+		return convertUnmarshal(val, retval.Addr())
+	}
+
+	if retval.Type().Kind() == reflect.Interface && !retval.IsNil() {
+		return convertUnmarshal(val, retval.Elem())
+	}
+
+	return false, nil
+}
+
+func convert(val string, retval reflect.Value, options multiTag) error {
+	if ok, err := convertUnmarshal(val, retval); ok {
+		return err
+	}
+
+	tp := retval.Type()
+
+	// Support for time.Duration
+	if tp == reflect.TypeOf((*time.Duration)(nil)).Elem() {
+		parsed, err := time.ParseDuration(val)
+
+		if err != nil {
+			return err
+		}
+
+		retval.SetInt(int64(parsed))
+		return nil
+	}
+
+	switch tp.Kind() {
+	case reflect.String:
+		retval.SetString(val)
+	case reflect.Bool:
+		if val == "" {
+			retval.SetBool(true)
+		} else {
+			b, err := strconv.ParseBool(val)
+
+			if err != nil {
+				return err
+			}
+
+			retval.SetBool(b)
+		}
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		base, err := getBase(options, 10)
+
+		if err != nil {
+			return err
+		}
+
+		parsed, err := strconv.ParseInt(val, base, tp.Bits())
+
+		if err != nil {
+			return err
+		}
+
+		retval.SetInt(parsed)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		base, err := getBase(options, 10)
+
+		if err != nil {
+			return err
+		}
+
+		parsed, err := strconv.ParseUint(val, base, tp.Bits())
+
+		if err != nil {
+			return err
+		}
+
+		retval.SetUint(parsed)
+	case reflect.Float32, reflect.Float64:
+		parsed, err := strconv.ParseFloat(val, tp.Bits())
+
+		if err != nil {
+			return err
+		}
+
+		retval.SetFloat(parsed)
+	case reflect.Slice:
+		elemtp := tp.Elem()
+
+		elemvalptr := reflect.New(elemtp)
+		elemval := reflect.Indirect(elemvalptr)
+
+		if err := convert(val, elemval, options); err != nil {
+			return err
+		}
+
+		retval.Set(reflect.Append(retval, elemval))
+	case reflect.Map:
+		parts := strings.SplitN(val, ":", 2)
+
+		key := parts[0]
+		var value string
+
+		if len(parts) == 2 {
+			value = parts[1]
+		}
+
+		keytp := tp.Key()
+		keyval := reflect.New(keytp)
+
+		if err := convert(key, keyval, options); err != nil {
+			return err
+		}
+
+		valuetp := tp.Elem()
+		valueval := reflect.New(valuetp)
+
+		if err := convert(value, valueval, options); err != nil {
+			return err
+		}
+
+		if retval.IsNil() {
+			retval.Set(reflect.MakeMap(tp))
+		}
+
+		retval.SetMapIndex(reflect.Indirect(keyval), reflect.Indirect(valueval))
+	case reflect.Ptr:
+		if retval.IsNil() {
+			retval.Set(reflect.New(retval.Type().Elem()))
+		}
+
+		return convert(val, reflect.Indirect(retval), options)
+	case reflect.Interface:
+		if !retval.IsNil() {
+			return convert(val, retval.Elem(), options)
+		}
+	}
+
+	return nil
+}
+
+func isPrint(s string) bool {
+	for _, c := range s {
+		if !strconv.IsPrint(c) {
+			return false
+		}
+	}
+
+	return true
+}
+
+func quoteIfNeeded(s string) string {
+	if !isPrint(s) {
+		return strconv.Quote(s)
+	}
+
+	return s
+}
+
+func quoteIfNeededV(s []string) []string {
+	ret := make([]string, len(s))
+
+	for i, v := range s {
+		ret[i] = quoteIfNeeded(v)
+	}
+
+	return ret
+}
+
+func quoteV(s []string) []string {
+	ret := make([]string, len(s))
+
+	for i, v := range s {
+		ret[i] = strconv.Quote(v)
+	}
+
+	return ret
+}
+
+func unquoteIfPossible(s string) (string, error) {
+	if len(s) == 0 || s[0] != '"' {
+		return s, nil
+	}
+
+	return strconv.Unquote(s)
+}
diff --git a/vendor/github.com/jessevdk/go-flags/error.go b/vendor/github.com/jessevdk/go-flags/error.go
new file mode 100644
index 0000000..05528d8
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/error.go
@@ -0,0 +1,134 @@
+package flags
+
+import (
+	"fmt"
+)
+
+// ErrorType represents the type of error.
+type ErrorType uint
+
+const (
+	// ErrUnknown indicates a generic error.
+	ErrUnknown ErrorType = iota
+
+	// ErrExpectedArgument indicates that an argument was expected.
+	ErrExpectedArgument
+
+	// ErrUnknownFlag indicates an unknown flag.
+	ErrUnknownFlag
+
+	// ErrUnknownGroup indicates an unknown group.
+	ErrUnknownGroup
+
+	// ErrMarshal indicates a marshalling error while converting values.
+	ErrMarshal
+
+	// ErrHelp indicates that the built-in help was shown (the error
+	// contains the help message).
+	ErrHelp
+
+	// ErrNoArgumentForBool indicates that an argument was given for a
+	// boolean flag (which don't not take any arguments).
+	ErrNoArgumentForBool
+
+	// ErrRequired indicates that a required flag was not provided.
+	ErrRequired
+
+	// ErrShortNameTooLong indicates that a short flag name was specified,
+	// longer than one character.
+	ErrShortNameTooLong
+
+	// ErrDuplicatedFlag indicates that a short or long flag has been
+	// defined more than once
+	ErrDuplicatedFlag
+
+	// ErrTag indicates an error while parsing flag tags.
+	ErrTag
+
+	// ErrCommandRequired indicates that a command was required but not
+	// specified
+	ErrCommandRequired
+
+	// ErrUnknownCommand indicates that an unknown command was specified.
+	ErrUnknownCommand
+
+	// ErrInvalidChoice indicates an invalid option value which only allows
+	// a certain number of choices.
+	ErrInvalidChoice
+
+	// ErrInvalidTag indicates an invalid tag or invalid use of an existing tag
+	ErrInvalidTag
+)
+
+func (e ErrorType) String() string {
+	switch e {
+	case ErrUnknown:
+		return "unknown"
+	case ErrExpectedArgument:
+		return "expected argument"
+	case ErrUnknownFlag:
+		return "unknown flag"
+	case ErrUnknownGroup:
+		return "unknown group"
+	case ErrMarshal:
+		return "marshal"
+	case ErrHelp:
+		return "help"
+	case ErrNoArgumentForBool:
+		return "no argument for bool"
+	case ErrRequired:
+		return "required"
+	case ErrShortNameTooLong:
+		return "short name too long"
+	case ErrDuplicatedFlag:
+		return "duplicated flag"
+	case ErrTag:
+		return "tag"
+	case ErrCommandRequired:
+		return "command required"
+	case ErrUnknownCommand:
+		return "unknown command"
+	case ErrInvalidChoice:
+		return "invalid choice"
+	case ErrInvalidTag:
+		return "invalid tag"
+	}
+
+	return "unrecognized error type"
+}
+
+// Error represents a parser error. The error returned from Parse is of this
+// type. The error contains both a Type and Message.
+type Error struct {
+	// The type of error
+	Type ErrorType
+
+	// The error message
+	Message string
+}
+
+// Error returns the error's message
+func (e *Error) Error() string {
+	return e.Message
+}
+
+func newError(tp ErrorType, message string) *Error {
+	return &Error{
+		Type:    tp,
+		Message: message,
+	}
+}
+
+func newErrorf(tp ErrorType, format string, args ...interface{}) *Error {
+	return newError(tp, fmt.Sprintf(format, args...))
+}
+
+func wrapError(err error) *Error {
+	ret, ok := err.(*Error)
+
+	if !ok {
+		return newError(ErrUnknown, err.Error())
+	}
+
+	return ret
+}
diff --git a/vendor/github.com/jessevdk/go-flags/flags.go b/vendor/github.com/jessevdk/go-flags/flags.go
new file mode 100644
index 0000000..889762d
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/flags.go
@@ -0,0 +1,258 @@
+// Copyright 2012 Jesse van den Kieboom. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package flags provides an extensive command line option parser.
+The flags package is similar in functionality to the go built-in flag package
+but provides more options and uses reflection to provide a convenient and
+succinct way of specifying command line options.
+
+
+Supported features
+
+The following features are supported in go-flags:
+
+    Options with short names (-v)
+    Options with long names (--verbose)
+    Options with and without arguments (bool v.s. other type)
+    Options with optional arguments and default values
+    Option default values from ENVIRONMENT_VARIABLES, including slice and map values
+    Multiple option groups each containing a set of options
+    Generate and print well-formatted help message
+    Passing remaining command line arguments after -- (optional)
+    Ignoring unknown command line options (optional)
+    Supports -I/usr/include -I=/usr/include -I /usr/include option argument specification
+    Supports multiple short options -aux
+    Supports all primitive go types (string, int{8..64}, uint{8..64}, float)
+    Supports same option multiple times (can store in slice or last option counts)
+    Supports maps
+    Supports function callbacks
+    Supports namespaces for (nested) option groups
+
+Additional features specific to Windows:
+    Options with short names (/v)
+    Options with long names (/verbose)
+    Windows-style options with arguments use a colon as the delimiter
+    Modify generated help message with Windows-style / options
+    Windows style options can be disabled at build time using the "forceposix"
+    build tag
+
+
+Basic usage
+
+The flags package uses structs, reflection and struct field tags
+to allow users to specify command line options. This results in very simple
+and concise specification of your application options. For example:
+
+    type Options struct {
+        Verbose []bool `short:"v" long:"verbose" description:"Show verbose debug information"`
+    }
+
+This specifies one option with a short name -v and a long name --verbose.
+When either -v or --verbose is found on the command line, a 'true' value
+will be appended to the Verbose field. e.g. when specifying -vvv, the
+resulting value of Verbose will be {[true, true, true]}.
+
+Slice options work exactly the same as primitive type options, except that
+whenever the option is encountered, a value is appended to the slice.
+
+Map options from string to primitive type are also supported. On the command
+line, you specify the value for such an option as key:value. For example
+
+    type Options struct {
+        AuthorInfo string[string] `short:"a"`
+    }
+
+Then, the AuthorInfo map can be filled with something like
+-a name:Jesse -a "surname:van den Kieboom".
+
+Finally, for full control over the conversion between command line argument
+values and options, user defined types can choose to implement the Marshaler
+and Unmarshaler interfaces.
+
+
+Available field tags
+
+The following is a list of tags for struct fields supported by go-flags:
+
+    short:            the short name of the option (single character)
+    long:             the long name of the option
+    required:         if non empty, makes the option required to appear on the command
+                      line. If a required option is not present, the parser will
+                      return ErrRequired (optional)
+    description:      the description of the option (optional)
+    long-description: the long description of the option. Currently only
+                      displayed in generated man pages (optional)
+    no-flag:          if non-empty, this field is ignored as an option (optional)
+
+    optional:       if non-empty, makes the argument of the option optional. When an
+                    argument is optional it can only be specified using
+                    --option=argument (optional)
+    optional-value: the value of an optional option when the option occurs
+                    without an argument. This tag can be specified multiple
+                    times in the case of maps or slices (optional)
+    default:        the default value of an option. This tag can be specified
+                    multiple times in the case of slices or maps (optional)
+    default-mask:   when specified, this value will be displayed in the help
+                    instead of the actual default value. This is useful
+                    mostly for hiding otherwise sensitive information from
+                    showing up in the help. If default-mask takes the special
+                    value "-", then no default value will be shown at all
+                    (optional)
+    env:            the default value of the option is overridden from the
+                    specified environment variable, if one has been defined.
+                    (optional)
+    env-delim:      the 'env' default value from environment is split into
+                    multiple values with the given delimiter string, use with
+                    slices and maps (optional)
+    value-name:     the name of the argument value (to be shown in the help)
+                    (optional)
+    choice:         limits the values for an option to a set of values.
+                    This tag can be specified multiple times (optional)
+    hidden:         if non-empty, the option is not visible in the help or man page.
+
+    base: a base (radix) used to convert strings to integer values, the
+          default base is 10 (i.e. decimal) (optional)
+
+    ini-name:       the explicit ini option name (optional)
+    no-ini:         if non-empty this field is ignored as an ini option
+                    (optional)
+
+    group:                when specified on a struct field, makes the struct
+                          field a separate group with the given name (optional)
+    namespace:            when specified on a group struct field, the namespace
+                          gets prepended to every option's long name and
+                          subgroup's namespace of this group, separated by
+                          the parser's namespace delimiter (optional)
+    command:              when specified on a struct field, makes the struct
+                          field a (sub)command with the given name (optional)
+    subcommands-optional: when specified on a command struct field, makes
+                          any subcommands of that command optional (optional)
+    alias:                when specified on a command struct field, adds the
+                          specified name as an alias for the command. Can be
+                          be specified multiple times to add more than one
+                          alias (optional)
+    positional-args:      when specified on a field with a struct type,
+                          uses the fields of that struct to parse remaining
+                          positional command line arguments into (in order
+                          of the fields). If a field has a slice type,
+                          then all remaining arguments will be added to it.
+                          Positional arguments are optional by default,
+                          unless the "required" tag is specified together
+                          with the "positional-args" tag. The "required" tag
+                          can also be set on the individual rest argument
+                          fields, to require only the first N positional
+                          arguments. If the "required" tag is set on the
+                          rest arguments slice, then its value determines
+                          the minimum amount of rest arguments that needs to
+                          be provided (e.g. `required:"2"`) (optional)
+    positional-arg-name:  used on a field in a positional argument struct; name
+                          of the positional argument placeholder to be shown in
+                          the help (optional)
+
+Either the `short:` tag or the `long:` must be specified to make the field eligible as an
+option.
+
+
+Option groups
+
+Option groups are a simple way to semantically separate your options. All
+options in a particular group are shown together in the help under the name
+of the group. Namespaces can be used to specify option long names more
+precisely and emphasize the options affiliation to their group.
+
+There are currently three ways to specify option groups.
+
+    1. Use NewNamedParser specifying the various option groups.
+    2. Use AddGroup to add a group to an existing parser.
+    3. Add a struct field to the top-level options annotated with the
+       group:"group-name" tag.
+
+
+
+Commands
+
+The flags package also has basic support for commands. Commands are often
+used in monolithic applications that support various commands or actions.
+Take git for example, all of the add, commit, checkout, etc. are called
+commands. Using commands you can easily separate multiple functions of your
+application.
+
+There are currently two ways to specify a command.
+
+    1. Use AddCommand on an existing parser.
+    2. Add a struct field to your options struct annotated with the
+       command:"command-name" tag.
+
+The most common, idiomatic way to implement commands is to define a global
+parser instance and implement each command in a separate file. These
+command files should define a go init function which calls AddCommand on
+the global parser.
+
+When parsing ends and there is an active command and that command implements
+the Commander interface, then its Execute method will be run with the
+remaining command line arguments.
+
+Command structs can have options which become valid to parse after the
+command has been specified on the command line, in addition to the options
+of all the parent commands. I.e. considering a -v flag on the parser and an
+add command, the following are equivalent:
+
+    ./app -v add
+    ./app add -v
+
+However, if the -v flag is defined on the add command, then the first of
+the two examples above would fail since the -v flag is not defined before
+the add command.
+
+
+Completion
+
+go-flags has builtin support to provide bash completion of flags, commands
+and argument values. To use completion, the binary which uses go-flags
+can be invoked in a special environment to list completion of the current
+command line argument. It should be noted that this `executes` your application,
+and it is up to the user to make sure there are no negative side effects (for
+example from init functions).
+
+Setting the environment variable `GO_FLAGS_COMPLETION=1` enables completion
+by replacing the argument parsing routine with the completion routine which
+outputs completions for the passed arguments. The basic invocation to
+complete a set of arguments is therefore:
+
+    GO_FLAGS_COMPLETION=1 ./completion-example arg1 arg2 arg3
+
+where `completion-example` is the binary, `arg1` and `arg2` are
+the current arguments, and `arg3` (the last argument) is the argument
+to be completed. If the GO_FLAGS_COMPLETION is set to "verbose", then
+descriptions of possible completion items will also be shown, if there
+are more than 1 completion items.
+
+To use this with bash completion, a simple file can be written which
+calls the binary which supports go-flags completion:
+
+    _completion_example() {
+        # All arguments except the first one
+        args=("${COMP_WORDS[@]:1:$COMP_CWORD}")
+
+        # Only split on newlines
+        local IFS=$'\n'
+
+        # Call completion (note that the first element of COMP_WORDS is
+        # the executable itself)
+        COMPREPLY=($(GO_FLAGS_COMPLETION=1 ${COMP_WORDS[0]} "${args[@]}"))
+        return 0
+    }
+
+    complete -F _completion_example completion-example
+
+Completion requires the parser option PassDoubleDash and is therefore enforced if the environment variable GO_FLAGS_COMPLETION is set.
+
+Customized completion for argument values is supported by implementing
+the flags.Completer interface for the argument value type. An example
+of a type which does so is the flags.Filename type, an alias of string
+allowing simple filename completion. A slice or array argument value
+whose element type implements flags.Completer will also be completed.
+*/
+package flags
diff --git a/vendor/github.com/jessevdk/go-flags/group.go b/vendor/github.com/jessevdk/go-flags/group.go
new file mode 100644
index 0000000..9e057ab
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/group.go
@@ -0,0 +1,406 @@
+// Copyright 2012 Jesse van den Kieboom. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flags
+
+import (
+	"errors"
+	"reflect"
+	"strings"
+	"unicode/utf8"
+)
+
+// ErrNotPointerToStruct indicates that a provided data container is not
+// a pointer to a struct. Only pointers to structs are valid data containers
+// for options.
+var ErrNotPointerToStruct = errors.New("provided data is not a pointer to struct")
+
+// Group represents an option group. Option groups can be used to logically
+// group options together under a description. Groups are only used to provide
+// more structure to options both for the user (as displayed in the help message)
+// and for you, since groups can be nested.
+type Group struct {
+	// A short description of the group. The
+	// short description is primarily used in the built-in generated help
+	// message
+	ShortDescription string
+
+	// A long description of the group. The long
+	// description is primarily used to present information on commands
+	// (Command embeds Group) in the built-in generated help and man pages.
+	LongDescription string
+
+	// The namespace of the group
+	Namespace string
+
+	// If true, the group is not displayed in the help or man page
+	Hidden bool
+
+	// The parent of the group or nil if it has no parent
+	parent interface{}
+
+	// All the options in the group
+	options []*Option
+
+	// All the subgroups
+	groups []*Group
+
+	// Whether the group represents the built-in help group
+	isBuiltinHelp bool
+
+	data interface{}
+}
+
+type scanHandler func(reflect.Value, *reflect.StructField) (bool, error)
+
+// AddGroup adds a new group to the command with the given name and data. The
+// data needs to be a pointer to a struct from which the fields indicate which
+// options are in the group.
+func (g *Group) AddGroup(shortDescription string, longDescription string, data interface{}) (*Group, error) {
+	group := newGroup(shortDescription, longDescription, data)
+
+	group.parent = g
+
+	if err := group.scan(); err != nil {
+		return nil, err
+	}
+
+	g.groups = append(g.groups, group)
+	return group, nil
+}
+
+// Groups returns the list of groups embedded in this group.
+func (g *Group) Groups() []*Group {
+	return g.groups
+}
+
+// Options returns the list of options in this group.
+func (g *Group) Options() []*Option {
+	return g.options
+}
+
+// Find locates the subgroup with the given short description and returns it.
+// If no such group can be found Find will return nil. Note that the description
+// is matched case insensitively.
+func (g *Group) Find(shortDescription string) *Group {
+	lshortDescription := strings.ToLower(shortDescription)
+
+	var ret *Group
+
+	g.eachGroup(func(gg *Group) {
+		if gg != g && strings.ToLower(gg.ShortDescription) == lshortDescription {
+			ret = gg
+		}
+	})
+
+	return ret
+}
+
+func (g *Group) findOption(matcher func(*Option) bool) (option *Option) {
+	g.eachGroup(func(g *Group) {
+		for _, opt := range g.options {
+			if option == nil && matcher(opt) {
+				option = opt
+			}
+		}
+	})
+
+	return option
+}
+
+// FindOptionByLongName finds an option that is part of the group, or any of its
+// subgroups, by matching its long name (including the option namespace).
+func (g *Group) FindOptionByLongName(longName string) *Option {
+	return g.findOption(func(option *Option) bool {
+		return option.LongNameWithNamespace() == longName
+	})
+}
+
+// FindOptionByShortName finds an option that is part of the group, or any of
+// its subgroups, by matching its short name.
+func (g *Group) FindOptionByShortName(shortName rune) *Option {
+	return g.findOption(func(option *Option) bool {
+		return option.ShortName == shortName
+	})
+}
+
+func newGroup(shortDescription string, longDescription string, data interface{}) *Group {
+	return &Group{
+		ShortDescription: shortDescription,
+		LongDescription:  longDescription,
+
+		data: data,
+	}
+}
+
+func (g *Group) optionByName(name string, namematch func(*Option, string) bool) *Option {
+	prio := 0
+	var retopt *Option
+
+	g.eachGroup(func(g *Group) {
+		for _, opt := range g.options {
+			if namematch != nil && namematch(opt, name) && prio < 4 {
+				retopt = opt
+				prio = 4
+			}
+
+			if name == opt.field.Name && prio < 3 {
+				retopt = opt
+				prio = 3
+			}
+
+			if name == opt.LongNameWithNamespace() && prio < 2 {
+				retopt = opt
+				prio = 2
+			}
+
+			if opt.ShortName != 0 && name == string(opt.ShortName) && prio < 1 {
+				retopt = opt
+				prio = 1
+			}
+		}
+	})
+
+	return retopt
+}
+
+func (g *Group) eachGroup(f func(*Group)) {
+	f(g)
+
+	for _, gg := range g.groups {
+		gg.eachGroup(f)
+	}
+}
+
+func isStringFalsy(s string) bool {
+	return s == "" || s == "false" || s == "no" || s == "0"
+}
+
+func (g *Group) scanStruct(realval reflect.Value, sfield *reflect.StructField, handler scanHandler) error {
+	stype := realval.Type()
+
+	if sfield != nil {
+		if ok, err := handler(realval, sfield); err != nil {
+			return err
+		} else if ok {
+			return nil
+		}
+	}
+
+	for i := 0; i < stype.NumField(); i++ {
+		field := stype.Field(i)
+
+		// PkgName is set only for non-exported fields, which we ignore
+		if field.PkgPath != "" && !field.Anonymous {
+			continue
+		}
+
+		mtag := newMultiTag(string(field.Tag))
+
+		if err := mtag.Parse(); err != nil {
+			return err
+		}
+
+		// Skip fields with the no-flag tag
+		if mtag.Get("no-flag") != "" {
+			continue
+		}
+
+		// Dive deep into structs or pointers to structs
+		kind := field.Type.Kind()
+		fld := realval.Field(i)
+
+		if kind == reflect.Struct {
+			if err := g.scanStruct(fld, &field, handler); err != nil {
+				return err
+			}
+		} else if kind == reflect.Ptr && field.Type.Elem().Kind() == reflect.Struct {
+			flagCountBefore := len(g.options) + len(g.groups)
+
+			if fld.IsNil() {
+				fld = reflect.New(fld.Type().Elem())
+			}
+
+			if err := g.scanStruct(reflect.Indirect(fld), &field, handler); err != nil {
+				return err
+			}
+
+			if len(g.options)+len(g.groups) != flagCountBefore {
+				realval.Field(i).Set(fld)
+			}
+		}
+
+		longname := mtag.Get("long")
+		shortname := mtag.Get("short")
+
+		// Need at least either a short or long name
+		if longname == "" && shortname == "" && mtag.Get("ini-name") == "" {
+			continue
+		}
+
+		short := rune(0)
+		rc := utf8.RuneCountInString(shortname)
+
+		if rc > 1 {
+			return newErrorf(ErrShortNameTooLong,
+				"short names can only be 1 character long, not `%s'",
+				shortname)
+
+		} else if rc == 1 {
+			short, _ = utf8.DecodeRuneInString(shortname)
+		}
+
+		description := mtag.Get("description")
+		def := mtag.GetMany("default")
+
+		optionalValue := mtag.GetMany("optional-value")
+		valueName := mtag.Get("value-name")
+		defaultMask := mtag.Get("default-mask")
+
+		optional := !isStringFalsy(mtag.Get("optional"))
+		required := !isStringFalsy(mtag.Get("required"))
+		choices := mtag.GetMany("choice")
+		hidden := !isStringFalsy(mtag.Get("hidden"))
+
+		option := &Option{
+			Description:      description,
+			ShortName:        short,
+			LongName:         longname,
+			Default:          def,
+			EnvDefaultKey:    mtag.Get("env"),
+			EnvDefaultDelim:  mtag.Get("env-delim"),
+			OptionalArgument: optional,
+			OptionalValue:    optionalValue,
+			Required:         required,
+			ValueName:        valueName,
+			DefaultMask:      defaultMask,
+			Choices:          choices,
+			Hidden:           hidden,
+
+			group: g,
+
+			field: field,
+			value: realval.Field(i),
+			tag:   mtag,
+		}
+
+		if option.isBool() && option.Default != nil {
+			return newErrorf(ErrInvalidTag,
+				"boolean flag `%s' may not have default values, they always default to `false' and can only be turned on",
+				option.shortAndLongName())
+		}
+
+		g.options = append(g.options, option)
+	}
+
+	return nil
+}
+
+func (g *Group) checkForDuplicateFlags() *Error {
+	shortNames := make(map[rune]*Option)
+	longNames := make(map[string]*Option)
+
+	var duplicateError *Error
+
+	g.eachGroup(func(g *Group) {
+		for _, option := range g.options {
+			if option.LongName != "" {
+				longName := option.LongNameWithNamespace()
+
+				if otherOption, ok := longNames[longName]; ok {
+					duplicateError = newErrorf(ErrDuplicatedFlag, "option `%s' uses the same long name as option `%s'", option, otherOption)
+					return
+				}
+				longNames[longName] = option
+			}
+			if option.ShortName != 0 {
+				if otherOption, ok := shortNames[option.ShortName]; ok {
+					duplicateError = newErrorf(ErrDuplicatedFlag, "option `%s' uses the same short name as option `%s'", option, otherOption)
+					return
+				}
+				shortNames[option.ShortName] = option
+			}
+		}
+	})
+
+	return duplicateError
+}
+
+func (g *Group) scanSubGroupHandler(realval reflect.Value, sfield *reflect.StructField) (bool, error) {
+	mtag := newMultiTag(string(sfield.Tag))
+
+	if err := mtag.Parse(); err != nil {
+		return true, err
+	}
+
+	subgroup := mtag.Get("group")
+
+	if len(subgroup) != 0 {
+		var ptrval reflect.Value
+
+		if realval.Kind() == reflect.Ptr {
+			ptrval = realval
+
+			if ptrval.IsNil() {
+				ptrval.Set(reflect.New(ptrval.Type()))
+			}
+		} else {
+			ptrval = realval.Addr()
+		}
+
+		description := mtag.Get("description")
+
+		group, err := g.AddGroup(subgroup, description, ptrval.Interface())
+
+		if err != nil {
+			return true, err
+		}
+
+		group.Namespace = mtag.Get("namespace")
+		group.Hidden = mtag.Get("hidden") != ""
+
+		return true, nil
+	}
+
+	return false, nil
+}
+
+func (g *Group) scanType(handler scanHandler) error {
+	// Get all the public fields in the data struct
+	ptrval := reflect.ValueOf(g.data)
+
+	if ptrval.Type().Kind() != reflect.Ptr {
+		panic(ErrNotPointerToStruct)
+	}
+
+	stype := ptrval.Type().Elem()
+
+	if stype.Kind() != reflect.Struct {
+		panic(ErrNotPointerToStruct)
+	}
+
+	realval := reflect.Indirect(ptrval)
+
+	if err := g.scanStruct(realval, nil, handler); err != nil {
+		return err
+	}
+
+	if err := g.checkForDuplicateFlags(); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (g *Group) scan() error {
+	return g.scanType(g.scanSubGroupHandler)
+}
+
+func (g *Group) groupByName(name string) *Group {
+	if len(name) == 0 {
+		return g
+	}
+
+	return g.Find(name)
+}
diff --git a/vendor/github.com/jessevdk/go-flags/help.go b/vendor/github.com/jessevdk/go-flags/help.go
new file mode 100644
index 0000000..d380305
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/help.go
@@ -0,0 +1,491 @@
+// Copyright 2012 Jesse van den Kieboom. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flags
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"runtime"
+	"strings"
+	"unicode/utf8"
+)
+
+type alignmentInfo struct {
+	maxLongLen      int
+	hasShort        bool
+	hasValueName    bool
+	terminalColumns int
+	indent          bool
+}
+
+const (
+	paddingBeforeOption                 = 2
+	distanceBetweenOptionAndDescription = 2
+)
+
+func (a *alignmentInfo) descriptionStart() int {
+	ret := a.maxLongLen + distanceBetweenOptionAndDescription
+
+	if a.hasShort {
+		ret += 2
+	}
+
+	if a.maxLongLen > 0 {
+		ret += 4
+	}
+
+	if a.hasValueName {
+		ret += 3
+	}
+
+	return ret
+}
+
+func (a *alignmentInfo) updateLen(name string, indent bool) {
+	l := utf8.RuneCountInString(name)
+
+	if indent {
+		l = l + 4
+	}
+
+	if l > a.maxLongLen {
+		a.maxLongLen = l
+	}
+}
+
+func (p *Parser) getAlignmentInfo() alignmentInfo {
+	ret := alignmentInfo{
+		maxLongLen:      0,
+		hasShort:        false,
+		hasValueName:    false,
+		terminalColumns: getTerminalColumns(),
+	}
+
+	if ret.terminalColumns <= 0 {
+		ret.terminalColumns = 80
+	}
+
+	var prevcmd *Command
+
+	p.eachActiveGroup(func(c *Command, grp *Group) {
+		if c != prevcmd {
+			for _, arg := range c.args {
+				ret.updateLen(arg.Name, c != p.Command)
+			}
+		}
+
+		for _, info := range grp.options {
+			if !info.canCli() {
+				continue
+			}
+
+			if info.ShortName != 0 {
+				ret.hasShort = true
+			}
+
+			if len(info.ValueName) > 0 {
+				ret.hasValueName = true
+			}
+
+			l := info.LongNameWithNamespace() + info.ValueName
+
+			if len(info.Choices) != 0 {
+				l += "[" + strings.Join(info.Choices, "|") + "]"
+			}
+
+			ret.updateLen(l, c != p.Command)
+		}
+	})
+
+	return ret
+}
+
+func wrapText(s string, l int, prefix string) string {
+	var ret string
+
+	if l < 10 {
+		l = 10
+	}
+
+	// Basic text wrapping of s at spaces to fit in l
+	lines := strings.Split(s, "\n")
+
+	for _, line := range lines {
+		var retline string
+
+		line = strings.TrimSpace(line)
+
+		for len(line) > l {
+			// Try to split on space
+			suffix := ""
+
+			pos := strings.LastIndex(line[:l], " ")
+
+			if pos < 0 {
+				pos = l - 1
+				suffix = "-\n"
+			}
+
+			if len(retline) != 0 {
+				retline += "\n" + prefix
+			}
+
+			retline += strings.TrimSpace(line[:pos]) + suffix
+			line = strings.TrimSpace(line[pos:])
+		}
+
+		if len(line) > 0 {
+			if len(retline) != 0 {
+				retline += "\n" + prefix
+			}
+
+			retline += line
+		}
+
+		if len(ret) > 0 {
+			ret += "\n"
+
+			if len(retline) > 0 {
+				ret += prefix
+			}
+		}
+
+		ret += retline
+	}
+
+	return ret
+}
+
+func (p *Parser) writeHelpOption(writer *bufio.Writer, option *Option, info alignmentInfo) {
+	line := &bytes.Buffer{}
+
+	prefix := paddingBeforeOption
+
+	if info.indent {
+		prefix += 4
+	}
+
+	if option.Hidden {
+		return
+	}
+
+	line.WriteString(strings.Repeat(" ", prefix))
+
+	if option.ShortName != 0 {
+		line.WriteRune(defaultShortOptDelimiter)
+		line.WriteRune(option.ShortName)
+	} else if info.hasShort {
+		line.WriteString("  ")
+	}
+
+	descstart := info.descriptionStart() + paddingBeforeOption
+
+	if len(option.LongName) > 0 {
+		if option.ShortName != 0 {
+			line.WriteString(", ")
+		} else if info.hasShort {
+			line.WriteString("  ")
+		}
+
+		line.WriteString(defaultLongOptDelimiter)
+		line.WriteString(option.LongNameWithNamespace())
+	}
+
+	if option.canArgument() {
+		line.WriteRune(defaultNameArgDelimiter)
+
+		if len(option.ValueName) > 0 {
+			line.WriteString(option.ValueName)
+		}
+
+		if len(option.Choices) > 0 {
+			line.WriteString("[" + strings.Join(option.Choices, "|") + "]")
+		}
+	}
+
+	written := line.Len()
+	line.WriteTo(writer)
+
+	if option.Description != "" {
+		dw := descstart - written
+		writer.WriteString(strings.Repeat(" ", dw))
+
+		var def string
+
+		if len(option.DefaultMask) != 0 {
+			if option.DefaultMask != "-" {
+				def = option.DefaultMask
+			}
+		} else {
+			def = option.defaultLiteral
+		}
+
+		var envDef string
+		if option.EnvDefaultKey != "" {
+			var envPrintable string
+			if runtime.GOOS == "windows" {
+				envPrintable = "%" + option.EnvDefaultKey + "%"
+			} else {
+				envPrintable = "$" + option.EnvDefaultKey
+			}
+			envDef = fmt.Sprintf(" [%s]", envPrintable)
+		}
+
+		var desc string
+
+		if def != "" {
+			desc = fmt.Sprintf("%s (default: %v)%s", option.Description, def, envDef)
+		} else {
+			desc = option.Description + envDef
+		}
+
+		writer.WriteString(wrapText(desc,
+			info.terminalColumns-descstart,
+			strings.Repeat(" ", descstart)))
+	}
+
+	writer.WriteString("\n")
+}
+
+func maxCommandLength(s []*Command) int {
+	if len(s) == 0 {
+		return 0
+	}
+
+	ret := len(s[0].Name)
+
+	for _, v := range s[1:] {
+		l := len(v.Name)
+
+		if l > ret {
+			ret = l
+		}
+	}
+
+	return ret
+}
+
+// WriteHelp writes a help message containing all the possible options and
+// their descriptions to the provided writer. Note that the HelpFlag parser
+// option provides a convenient way to add a -h/--help option group to the
+// command line parser which will automatically show the help messages using
+// this method.
+func (p *Parser) WriteHelp(writer io.Writer) {
+	if writer == nil {
+		return
+	}
+
+	wr := bufio.NewWriter(writer)
+	aligninfo := p.getAlignmentInfo()
+
+	cmd := p.Command
+
+	for cmd.Active != nil {
+		cmd = cmd.Active
+	}
+
+	if p.Name != "" {
+		wr.WriteString("Usage:\n")
+		wr.WriteString(" ")
+
+		allcmd := p.Command
+
+		for allcmd != nil {
+			var usage string
+
+			if allcmd == p.Command {
+				if len(p.Usage) != 0 {
+					usage = p.Usage
+				} else if p.Options&HelpFlag != 0 {
+					usage = "[OPTIONS]"
+				}
+			} else if us, ok := allcmd.data.(Usage); ok {
+				usage = us.Usage()
+			} else if allcmd.hasCliOptions() {
+				usage = fmt.Sprintf("[%s-OPTIONS]", allcmd.Name)
+			}
+
+			if len(usage) != 0 {
+				fmt.Fprintf(wr, " %s %s", allcmd.Name, usage)
+			} else {
+				fmt.Fprintf(wr, " %s", allcmd.Name)
+			}
+
+			if len(allcmd.args) > 0 {
+				fmt.Fprintf(wr, " ")
+			}
+
+			for i, arg := range allcmd.args {
+				if i != 0 {
+					fmt.Fprintf(wr, " ")
+				}
+
+				name := arg.Name
+
+				if arg.isRemaining() {
+					name = name + "..."
+				}
+
+				if !allcmd.ArgsRequired {
+					fmt.Fprintf(wr, "[%s]", name)
+				} else {
+					fmt.Fprintf(wr, "%s", name)
+				}
+			}
+
+			if allcmd.Active == nil && len(allcmd.commands) > 0 {
+				var co, cc string
+
+				if allcmd.SubcommandsOptional {
+					co, cc = "[", "]"
+				} else {
+					co, cc = "<", ">"
+				}
+
+				visibleCommands := allcmd.visibleCommands()
+
+				if len(visibleCommands) > 3 {
+					fmt.Fprintf(wr, " %scommand%s", co, cc)
+				} else {
+					subcommands := allcmd.sortedVisibleCommands()
+					names := make([]string, len(subcommands))
+
+					for i, subc := range subcommands {
+						names[i] = subc.Name
+					}
+
+					fmt.Fprintf(wr, " %s%s%s", co, strings.Join(names, " | "), cc)
+				}
+			}
+
+			allcmd = allcmd.Active
+		}
+
+		fmt.Fprintln(wr)
+
+		if len(cmd.LongDescription) != 0 {
+			fmt.Fprintln(wr)
+
+			t := wrapText(cmd.LongDescription,
+				aligninfo.terminalColumns,
+				"")
+
+			fmt.Fprintln(wr, t)
+		}
+	}
+
+	c := p.Command
+
+	for c != nil {
+		printcmd := c != p.Command
+
+		c.eachGroup(func(grp *Group) {
+			first := true
+
+			// Skip built-in help group for all commands except the top-level
+			// parser
+			if grp.Hidden || (grp.isBuiltinHelp && c != p.Command) {
+				return
+			}
+
+			for _, info := range grp.options {
+				if !info.canCli() || info.Hidden {
+					continue
+				}
+
+				if printcmd {
+					fmt.Fprintf(wr, "\n[%s command options]\n", c.Name)
+					aligninfo.indent = true
+					printcmd = false
+				}
+
+				if first && cmd.Group != grp {
+					fmt.Fprintln(wr)
+
+					if aligninfo.indent {
+						wr.WriteString("    ")
+					}
+
+					fmt.Fprintf(wr, "%s:\n", grp.ShortDescription)
+					first = false
+				}
+
+				p.writeHelpOption(wr, info, aligninfo)
+			}
+		})
+
+		var args []*Arg
+		for _, arg := range c.args {
+			if arg.Description != "" {
+				args = append(args, arg)
+			}
+		}
+
+		if len(args) > 0 {
+			if c == p.Command {
+				fmt.Fprintf(wr, "\nArguments:\n")
+			} else {
+				fmt.Fprintf(wr, "\n[%s command arguments]\n", c.Name)
+			}
+
+			descStart := aligninfo.descriptionStart() + paddingBeforeOption
+
+			for _, arg := range args {
+				argPrefix := strings.Repeat(" ", paddingBeforeOption)
+				argPrefix += arg.Name
+
+				if len(arg.Description) > 0 {
+					argPrefix += ":"
+					wr.WriteString(argPrefix)
+
+					// Space between "arg:" and the description start
+					descPadding := strings.Repeat(" ", descStart-len(argPrefix))
+					// How much space the description gets before wrapping
+					descWidth := aligninfo.terminalColumns - 1 - descStart
+					// Whitespace to which we can indent new description lines
+					descPrefix := strings.Repeat(" ", descStart)
+
+					wr.WriteString(descPadding)
+					wr.WriteString(wrapText(arg.Description, descWidth, descPrefix))
+				} else {
+					wr.WriteString(argPrefix)
+				}
+
+				fmt.Fprintln(wr)
+			}
+		}
+
+		c = c.Active
+	}
+
+	scommands := cmd.sortedVisibleCommands()
+
+	if len(scommands) > 0 {
+		maxnamelen := maxCommandLength(scommands)
+
+		fmt.Fprintln(wr)
+		fmt.Fprintln(wr, "Available commands:")
+
+		for _, c := range scommands {
+			fmt.Fprintf(wr, "  %s", c.Name)
+
+			if len(c.ShortDescription) > 0 {
+				pad := strings.Repeat(" ", maxnamelen-len(c.Name))
+				fmt.Fprintf(wr, "%s  %s", pad, c.ShortDescription)
+
+				if len(c.Aliases) > 0 {
+					fmt.Fprintf(wr, " (aliases: %s)", strings.Join(c.Aliases, ", "))
+				}
+
+			}
+
+			fmt.Fprintln(wr)
+		}
+	}
+
+	wr.Flush()
+}
diff --git a/vendor/github.com/jessevdk/go-flags/ini.go b/vendor/github.com/jessevdk/go-flags/ini.go
new file mode 100644
index 0000000..e714d3d
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/ini.go
@@ -0,0 +1,597 @@
+package flags
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"reflect"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+// IniError contains location information on where an error occurred.
+type IniError struct {
+	// The error message.
+	Message string
+
+	// The filename of the file in which the error occurred.
+	File string
+
+	// The line number at which the error occurred.
+	LineNumber uint
+}
+
+// Error provides a "file:line: message" formatted message of the ini error.
+func (x *IniError) Error() string {
+	return fmt.Sprintf(
+		"%s:%d: %s",
+		x.File,
+		x.LineNumber,
+		x.Message,
+	)
+}
+
+// IniOptions for writing
+type IniOptions uint
+
+const (
+	// IniNone indicates no options.
+	IniNone IniOptions = 0
+
+	// IniIncludeDefaults indicates that default values should be written.
+	IniIncludeDefaults = 1 << iota
+
+	// IniCommentDefaults indicates that if IniIncludeDefaults is used
+	// options with default values are written but commented out.
+	IniCommentDefaults
+
+	// IniIncludeComments indicates that comments containing the description
+	// of an option should be written.
+	IniIncludeComments
+
+	// IniDefault provides a default set of options.
+	IniDefault = IniIncludeComments
+)
+
+// IniParser is a utility to read and write flags options from and to ini
+// formatted strings.
+type IniParser struct {
+	ParseAsDefaults bool // override default flags
+
+	parser *Parser
+}
+
+type iniValue struct {
+	Name       string
+	Value      string
+	Quoted     bool
+	LineNumber uint
+}
+
+type iniSection []iniValue
+
+type ini struct {
+	File     string
+	Sections map[string]iniSection
+}
+
+// NewIniParser creates a new ini parser for a given Parser.
+func NewIniParser(p *Parser) *IniParser {
+	return &IniParser{
+		parser: p,
+	}
+}
+
+// IniParse is a convenience function to parse command line options with default
+// settings from an ini formatted file. The provided data is a pointer to a struct
+// representing the default option group (named "Application Options"). For
+// more control, use flags.NewParser.
+func IniParse(filename string, data interface{}) error {
+	p := NewParser(data, Default)
+
+	return NewIniParser(p).ParseFile(filename)
+}
+
+// ParseFile parses flags from an ini formatted file. See Parse for more
+// information on the ini file format. The returned errors can be of the type
+// flags.Error or flags.IniError.
+func (i *IniParser) ParseFile(filename string) error {
+	ini, err := readIniFromFile(filename)
+
+	if err != nil {
+		return err
+	}
+
+	return i.parse(ini)
+}
+
+// Parse parses flags from an ini format. You can use ParseFile as a
+// convenience function to parse from a filename instead of a general
+// io.Reader.
+//
+// The format of the ini file is as follows:
+//
+//     [Option group name]
+//     option = value
+//
+// Each section in the ini file represents an option group or command in the
+// flags parser. The default flags parser option group (i.e. when using
+// flags.Parse) is named 'Application Options'. The ini option name is matched
+// in the following order:
+//
+//     1. Compared to the ini-name tag on the option struct field (if present)
+//     2. Compared to the struct field name
+//     3. Compared to the option long name (if present)
+//     4. Compared to the option short name (if present)
+//
+// Sections for nested groups and commands can be addressed using a dot `.'
+// namespacing notation (i.e [subcommand.Options]). Group section names are
+// matched case insensitive.
+//
+// The returned errors can be of the type flags.Error or flags.IniError.
+func (i *IniParser) Parse(reader io.Reader) error {
+	ini, err := readIni(reader, "")
+
+	if err != nil {
+		return err
+	}
+
+	return i.parse(ini)
+}
+
+// WriteFile writes the flags as ini format into a file. See Write
+// for more information. The returned error occurs when the specified file
+// could not be opened for writing.
+func (i *IniParser) WriteFile(filename string, options IniOptions) error {
+	return writeIniToFile(i, filename, options)
+}
+
+// Write writes the current values of all the flags to an ini format.
+// See Parse for more information on the ini file format. You typically
+// call this only after settings have been parsed since the default values of each
+// option are stored just before parsing the flags (this is only relevant when
+// IniIncludeDefaults is _not_ set in options).
+func (i *IniParser) Write(writer io.Writer, options IniOptions) {
+	writeIni(i, writer, options)
+}
+
+func readFullLine(reader *bufio.Reader) (string, error) {
+	var line []byte
+
+	for {
+		l, more, err := reader.ReadLine()
+
+		if err != nil {
+			return "", err
+		}
+
+		if line == nil && !more {
+			return string(l), nil
+		}
+
+		line = append(line, l...)
+
+		if !more {
+			break
+		}
+	}
+
+	return string(line), nil
+}
+
+func optionIniName(option *Option) string {
+	name := option.tag.Get("_read-ini-name")
+
+	if len(name) != 0 {
+		return name
+	}
+
+	name = option.tag.Get("ini-name")
+
+	if len(name) != 0 {
+		return name
+	}
+
+	return option.field.Name
+}
+
+func writeGroupIni(cmd *Command, group *Group, namespace string, writer io.Writer, options IniOptions) {
+	var sname string
+
+	if len(namespace) != 0 {
+		sname = namespace
+	}
+
+	if cmd.Group != group && len(group.ShortDescription) != 0 {
+		if len(sname) != 0 {
+			sname += "."
+		}
+
+		sname += group.ShortDescription
+	}
+
+	sectionwritten := false
+	comments := (options & IniIncludeComments) != IniNone
+
+	for _, option := range group.options {
+		if option.isFunc() || option.Hidden {
+			continue
+		}
+
+		if len(option.tag.Get("no-ini")) != 0 {
+			continue
+		}
+
+		val := option.value
+
+		if (options&IniIncludeDefaults) == IniNone && option.valueIsDefault() {
+			continue
+		}
+
+		if !sectionwritten {
+			fmt.Fprintf(writer, "[%s]\n", sname)
+			sectionwritten = true
+		}
+
+		if comments && len(option.Description) != 0 {
+			fmt.Fprintf(writer, "; %s\n", option.Description)
+		}
+
+		oname := optionIniName(option)
+
+		commentOption := (options&(IniIncludeDefaults|IniCommentDefaults)) == IniIncludeDefaults|IniCommentDefaults && option.valueIsDefault()
+
+		kind := val.Type().Kind()
+		switch kind {
+		case reflect.Slice:
+			kind = val.Type().Elem().Kind()
+
+			if val.Len() == 0 {
+				writeOption(writer, oname, kind, "", "", true, option.iniQuote)
+			} else {
+				for idx := 0; idx < val.Len(); idx++ {
+					v, _ := convertToString(val.Index(idx), option.tag)
+
+					writeOption(writer, oname, kind, "", v, commentOption, option.iniQuote)
+				}
+			}
+		case reflect.Map:
+			kind = val.Type().Elem().Kind()
+
+			if val.Len() == 0 {
+				writeOption(writer, oname, kind, "", "", true, option.iniQuote)
+			} else {
+				mkeys := val.MapKeys()
+				keys := make([]string, len(val.MapKeys()))
+				kkmap := make(map[string]reflect.Value)
+
+				for i, k := range mkeys {
+					keys[i], _ = convertToString(k, option.tag)
+					kkmap[keys[i]] = k
+				}
+
+				sort.Strings(keys)
+
+				for _, k := range keys {
+					v, _ := convertToString(val.MapIndex(kkmap[k]), option.tag)
+
+					writeOption(writer, oname, kind, k, v, commentOption, option.iniQuote)
+				}
+			}
+		default:
+			v, _ := convertToString(val, option.tag)
+
+			writeOption(writer, oname, kind, "", v, commentOption, option.iniQuote)
+		}
+
+		if comments {
+			fmt.Fprintln(writer)
+		}
+	}
+
+	if sectionwritten && !comments {
+		fmt.Fprintln(writer)
+	}
+}
+
+func writeOption(writer io.Writer, optionName string, optionType reflect.Kind, optionKey string, optionValue string, commentOption bool, forceQuote bool) {
+	if forceQuote || (optionType == reflect.String && !isPrint(optionValue)) {
+		optionValue = strconv.Quote(optionValue)
+	}
+
+	comment := ""
+	if commentOption {
+		comment = "; "
+	}
+
+	fmt.Fprintf(writer, "%s%s =", comment, optionName)
+
+	if optionKey != "" {
+		fmt.Fprintf(writer, " %s:%s", optionKey, optionValue)
+	} else if optionValue != "" {
+		fmt.Fprintf(writer, " %s", optionValue)
+	}
+
+	fmt.Fprintln(writer)
+}
+
+func writeCommandIni(command *Command, namespace string, writer io.Writer, options IniOptions) {
+	command.eachGroup(func(group *Group) {
+		if !group.Hidden {
+			writeGroupIni(command, group, namespace, writer, options)
+		}
+	})
+
+	for _, c := range command.commands {
+		var nns string
+
+		if c.Hidden {
+			continue
+		}
+
+		if len(namespace) != 0 {
+			nns = c.Name + "." + nns
+		} else {
+			nns = c.Name
+		}
+
+		writeCommandIni(c, nns, writer, options)
+	}
+}
+
+func writeIni(parser *IniParser, writer io.Writer, options IniOptions) {
+	writeCommandIni(parser.parser.Command, "", writer, options)
+}
+
+func writeIniToFile(parser *IniParser, filename string, options IniOptions) error {
+	file, err := os.Create(filename)
+
+	if err != nil {
+		return err
+	}
+
+	defer file.Close()
+
+	writeIni(parser, file, options)
+
+	return nil
+}
+
+func readIniFromFile(filename string) (*ini, error) {
+	file, err := os.Open(filename)
+
+	if err != nil {
+		return nil, err
+	}
+
+	defer file.Close()
+
+	return readIni(file, filename)
+}
+
+func readIni(contents io.Reader, filename string) (*ini, error) {
+	ret := &ini{
+		File:     filename,
+		Sections: make(map[string]iniSection),
+	}
+
+	reader := bufio.NewReader(contents)
+
+	// Empty global section
+	section := make(iniSection, 0, 10)
+	sectionname := ""
+
+	ret.Sections[sectionname] = section
+
+	var lineno uint
+
+	for {
+		line, err := readFullLine(reader)
+
+		if err == io.EOF {
+			break
+		} else if err != nil {
+			return nil, err
+		}
+
+		lineno++
+		line = strings.TrimSpace(line)
+
+		// Skip empty lines and lines starting with ; (comments)
+		if len(line) == 0 || line[0] == ';' || line[0] == '#' {
+			continue
+		}
+
+		if line[0] == '[' {
+			if line[0] != '[' || line[len(line)-1] != ']' {
+				return nil, &IniError{
+					Message:    "malformed section header",
+					File:       filename,
+					LineNumber: lineno,
+				}
+			}
+
+			name := strings.TrimSpace(line[1 : len(line)-1])
+
+			if len(name) == 0 {
+				return nil, &IniError{
+					Message:    "empty section name",
+					File:       filename,
+					LineNumber: lineno,
+				}
+			}
+
+			sectionname = name
+			section = ret.Sections[name]
+
+			if section == nil {
+				section = make(iniSection, 0, 10)
+				ret.Sections[name] = section
+			}
+
+			continue
+		}
+
+		// Parse option here
+		keyval := strings.SplitN(line, "=", 2)
+
+		if len(keyval) != 2 {
+			return nil, &IniError{
+				Message:    fmt.Sprintf("malformed key=value (%s)", line),
+				File:       filename,
+				LineNumber: lineno,
+			}
+		}
+
+		name := strings.TrimSpace(keyval[0])
+		value := strings.TrimSpace(keyval[1])
+		quoted := false
+
+		if len(value) != 0 && value[0] == '"' {
+			if v, err := strconv.Unquote(value); err == nil {
+				value = v
+
+				quoted = true
+			} else {
+				return nil, &IniError{
+					Message:    err.Error(),
+					File:       filename,
+					LineNumber: lineno,
+				}
+			}
+		}
+
+		section = append(section, iniValue{
+			Name:       name,
+			Value:      value,
+			Quoted:     quoted,
+			LineNumber: lineno,
+		})
+
+		ret.Sections[sectionname] = section
+	}
+
+	return ret, nil
+}
+
+func (i *IniParser) matchingGroups(name string) []*Group {
+	if len(name) == 0 {
+		var ret []*Group
+
+		i.parser.eachGroup(func(g *Group) {
+			ret = append(ret, g)
+		})
+
+		return ret
+	}
+
+	g := i.parser.groupByName(name)
+
+	if g != nil {
+		return []*Group{g}
+	}
+
+	return nil
+}
+
+func (i *IniParser) parse(ini *ini) error {
+	p := i.parser
+
+	var quotesLookup = make(map[*Option]bool)
+
+	for name, section := range ini.Sections {
+		groups := i.matchingGroups(name)
+
+		if len(groups) == 0 {
+			return newErrorf(ErrUnknownGroup, "could not find option group `%s'", name)
+		}
+
+		for _, inival := range section {
+			var opt *Option
+
+			for _, group := range groups {
+				opt = group.optionByName(inival.Name, func(o *Option, n string) bool {
+					return strings.ToLower(o.tag.Get("ini-name")) == strings.ToLower(n)
+				})
+
+				if opt != nil && len(opt.tag.Get("no-ini")) != 0 {
+					opt = nil
+				}
+
+				if opt != nil {
+					break
+				}
+			}
+
+			if opt == nil {
+				if (p.Options & IgnoreUnknown) == None {
+					return &IniError{
+						Message:    fmt.Sprintf("unknown option: %s", inival.Name),
+						File:       ini.File,
+						LineNumber: inival.LineNumber,
+					}
+				}
+
+				continue
+			}
+
+			// ini value is ignored if override is set and
+			// value was previously set from non default
+			if i.ParseAsDefaults && !opt.isSetDefault {
+				continue
+			}
+
+			pval := &inival.Value
+
+			if !opt.canArgument() && len(inival.Value) == 0 {
+				pval = nil
+			} else {
+				if opt.value.Type().Kind() == reflect.Map {
+					parts := strings.SplitN(inival.Value, ":", 2)
+
+					// only handle unquoting
+					if len(parts) == 2 && parts[1][0] == '"' {
+						if v, err := strconv.Unquote(parts[1]); err == nil {
+							parts[1] = v
+
+							inival.Quoted = true
+						} else {
+							return &IniError{
+								Message:    err.Error(),
+								File:       ini.File,
+								LineNumber: inival.LineNumber,
+							}
+						}
+
+						s := parts[0] + ":" + parts[1]
+
+						pval = &s
+					}
+				}
+			}
+
+			if err := opt.set(pval); err != nil {
+				return &IniError{
+					Message:    err.Error(),
+					File:       ini.File,
+					LineNumber: inival.LineNumber,
+				}
+			}
+
+			// either all INI values are quoted or only values who need quoting
+			if _, ok := quotesLookup[opt]; !inival.Quoted || !ok {
+				quotesLookup[opt] = inival.Quoted
+			}
+
+			opt.tag.Set("_read-ini-name", inival.Name)
+		}
+	}
+
+	for opt, quoted := range quotesLookup {
+		opt.iniQuote = quoted
+	}
+
+	return nil
+}
diff --git a/vendor/github.com/jessevdk/go-flags/man.go b/vendor/github.com/jessevdk/go-flags/man.go
new file mode 100644
index 0000000..0cb114e
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/man.go
@@ -0,0 +1,205 @@
+package flags
+
+import (
+	"fmt"
+	"io"
+	"runtime"
+	"strings"
+	"time"
+)
+
+func manQuote(s string) string {
+	return strings.Replace(s, "\\", "\\\\", -1)
+}
+
+func formatForMan(wr io.Writer, s string) {
+	for {
+		idx := strings.IndexRune(s, '`')
+
+		if idx < 0 {
+			fmt.Fprintf(wr, "%s", manQuote(s))
+			break
+		}
+
+		fmt.Fprintf(wr, "%s", manQuote(s[:idx]))
+
+		s = s[idx+1:]
+		idx = strings.IndexRune(s, '\'')
+
+		if idx < 0 {
+			fmt.Fprintf(wr, "%s", manQuote(s))
+			break
+		}
+
+		fmt.Fprintf(wr, "\\fB%s\\fP", manQuote(s[:idx]))
+		s = s[idx+1:]
+	}
+}
+
+func writeManPageOptions(wr io.Writer, grp *Group) {
+	grp.eachGroup(func(group *Group) {
+		if group.Hidden || len(group.options) == 0 {
+			return
+		}
+
+		// If the parent (grp) has any subgroups, display their descriptions as
+		// subsection headers similar to the output of --help.
+		if group.ShortDescription != "" && len(grp.groups) > 0 {
+			fmt.Fprintf(wr, ".SS %s\n", group.ShortDescription)
+
+			if group.LongDescription != "" {
+				formatForMan(wr, group.LongDescription)
+				fmt.Fprintln(wr, "")
+			}
+		}
+
+		for _, opt := range group.options {
+			if !opt.canCli() || opt.Hidden {
+				continue
+			}
+
+			fmt.Fprintln(wr, ".TP")
+			fmt.Fprintf(wr, "\\fB")
+
+			if opt.ShortName != 0 {
+				fmt.Fprintf(wr, "\\fB\\-%c\\fR", opt.ShortName)
+			}
+
+			if len(opt.LongName) != 0 {
+				if opt.ShortName != 0 {
+					fmt.Fprintf(wr, ", ")
+				}
+
+				fmt.Fprintf(wr, "\\fB\\-\\-%s\\fR", manQuote(opt.LongNameWithNamespace()))
+			}
+
+			if len(opt.ValueName) != 0 || opt.OptionalArgument {
+				if opt.OptionalArgument {
+					fmt.Fprintf(wr, " [\\fI%s=%s\\fR]", manQuote(opt.ValueName), manQuote(strings.Join(quoteV(opt.OptionalValue), ", ")))
+				} else {
+					fmt.Fprintf(wr, " \\fI%s\\fR", manQuote(opt.ValueName))
+				}
+			}
+
+			if len(opt.Default) != 0 {
+				fmt.Fprintf(wr, " <default: \\fI%s\\fR>", manQuote(strings.Join(quoteV(opt.Default), ", ")))
+			} else if len(opt.EnvDefaultKey) != 0 {
+				if runtime.GOOS == "windows" {
+					fmt.Fprintf(wr, " <default: \\fI%%%s%%\\fR>", manQuote(opt.EnvDefaultKey))
+				} else {
+					fmt.Fprintf(wr, " <default: \\fI$%s\\fR>", manQuote(opt.EnvDefaultKey))
+				}
+			}
+
+			if opt.Required {
+				fmt.Fprintf(wr, " (\\fIrequired\\fR)")
+			}
+
+			fmt.Fprintln(wr, "\\fP")
+
+			if len(opt.Description) != 0 {
+				formatForMan(wr, opt.Description)
+				fmt.Fprintln(wr, "")
+			}
+		}
+	})
+}
+
+func writeManPageSubcommands(wr io.Writer, name string, root *Command) {
+	commands := root.sortedVisibleCommands()
+
+	for _, c := range commands {
+		var nn string
+
+		if c.Hidden {
+			continue
+		}
+
+		if len(name) != 0 {
+			nn = name + " " + c.Name
+		} else {
+			nn = c.Name
+		}
+
+		writeManPageCommand(wr, nn, root, c)
+	}
+}
+
+func writeManPageCommand(wr io.Writer, name string, root *Command, command *Command) {
+	fmt.Fprintf(wr, ".SS %s\n", name)
+	fmt.Fprintln(wr, command.ShortDescription)
+
+	if len(command.LongDescription) > 0 {
+		fmt.Fprintln(wr, "")
+
+		cmdstart := fmt.Sprintf("The %s command", manQuote(command.Name))
+
+		if strings.HasPrefix(command.LongDescription, cmdstart) {
+			fmt.Fprintf(wr, "The \\fI%s\\fP command", manQuote(command.Name))
+
+			formatForMan(wr, command.LongDescription[len(cmdstart):])
+			fmt.Fprintln(wr, "")
+		} else {
+			formatForMan(wr, command.LongDescription)
+			fmt.Fprintln(wr, "")
+		}
+	}
+
+	var usage string
+	if us, ok := command.data.(Usage); ok {
+		usage = us.Usage()
+	} else if command.hasCliOptions() {
+		usage = fmt.Sprintf("[%s-OPTIONS]", command.Name)
+	}
+
+	var pre string
+	if root.hasCliOptions() {
+		pre = fmt.Sprintf("%s [OPTIONS] %s", root.Name, command.Name)
+	} else {
+		pre = fmt.Sprintf("%s %s", root.Name, command.Name)
+	}
+
+	if len(usage) > 0 {
+		fmt.Fprintf(wr, "\n\\fBUsage\\fP: %s %s\n.TP\n", manQuote(pre), manQuote(usage))
+	}
+
+	if len(command.Aliases) > 0 {
+		fmt.Fprintf(wr, "\n\\fBAliases\\fP: %s\n\n", manQuote(strings.Join(command.Aliases, ", ")))
+	}
+
+	writeManPageOptions(wr, command.Group)
+	writeManPageSubcommands(wr, name, command)
+}
+
+// WriteManPage writes a basic man page in groff format to the specified
+// writer.
+func (p *Parser) WriteManPage(wr io.Writer) {
+	t := time.Now()
+
+	fmt.Fprintf(wr, ".TH %s 1 \"%s\"\n", manQuote(p.Name), t.Format("2 January 2006"))
+	fmt.Fprintln(wr, ".SH NAME")
+	fmt.Fprintf(wr, "%s \\- %s\n", manQuote(p.Name), manQuote(p.ShortDescription))
+	fmt.Fprintln(wr, ".SH SYNOPSIS")
+
+	usage := p.Usage
+
+	if len(usage) == 0 {
+		usage = "[OPTIONS]"
+	}
+
+	fmt.Fprintf(wr, "\\fB%s\\fP %s\n", manQuote(p.Name), manQuote(usage))
+	fmt.Fprintln(wr, ".SH DESCRIPTION")
+
+	formatForMan(wr, p.LongDescription)
+	fmt.Fprintln(wr, "")
+
+	fmt.Fprintln(wr, ".SH OPTIONS")
+
+	writeManPageOptions(wr, p.Command.Group)
+
+	if len(p.visibleCommands()) > 0 {
+		fmt.Fprintln(wr, ".SH COMMANDS")
+
+		writeManPageSubcommands(wr, "", p.Command)
+	}
+}
diff --git a/vendor/github.com/jessevdk/go-flags/multitag.go b/vendor/github.com/jessevdk/go-flags/multitag.go
new file mode 100644
index 0000000..96bb1a3
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/multitag.go
@@ -0,0 +1,140 @@
+package flags
+
+import (
+	"strconv"
+)
+
+type multiTag struct {
+	value string
+	cache map[string][]string
+}
+
+func newMultiTag(v string) multiTag {
+	return multiTag{
+		value: v,
+	}
+}
+
+func (x *multiTag) scan() (map[string][]string, error) {
+	v := x.value
+
+	ret := make(map[string][]string)
+
+	// This is mostly copied from reflect.StructTag.Get
+	for v != "" {
+		i := 0
+
+		// Skip whitespace
+		for i < len(v) && v[i] == ' ' {
+			i++
+		}
+
+		v = v[i:]
+
+		if v == "" {
+			break
+		}
+
+		// Scan to colon to find key
+		i = 0
+
+		for i < len(v) && v[i] != ' ' && v[i] != ':' && v[i] != '"' {
+			i++
+		}
+
+		if i >= len(v) {
+			return nil, newErrorf(ErrTag, "expected `:' after key name, but got end of tag (in `%v`)", x.value)
+		}
+
+		if v[i] != ':' {
+			return nil, newErrorf(ErrTag, "expected `:' after key name, but got `%v' (in `%v`)", v[i], x.value)
+		}
+
+		if i+1 >= len(v) {
+			return nil, newErrorf(ErrTag, "expected `\"' to start tag value at end of tag (in `%v`)", x.value)
+		}
+
+		if v[i+1] != '"' {
+			return nil, newErrorf(ErrTag, "expected `\"' to start tag value, but got `%v' (in `%v`)", v[i+1], x.value)
+		}
+
+		name := v[:i]
+		v = v[i+1:]
+
+		// Scan quoted string to find value
+		i = 1
+
+		for i < len(v) && v[i] != '"' {
+			if v[i] == '\n' {
+				return nil, newErrorf(ErrTag, "unexpected newline in tag value `%v' (in `%v`)", name, x.value)
+			}
+
+			if v[i] == '\\' {
+				i++
+			}
+			i++
+		}
+
+		if i >= len(v) {
+			return nil, newErrorf(ErrTag, "expected end of tag value `\"' at end of tag (in `%v`)", x.value)
+		}
+
+		val, err := strconv.Unquote(v[:i+1])
+
+		if err != nil {
+			return nil, newErrorf(ErrTag, "Malformed value of tag `%v:%v` => %v (in `%v`)", name, v[:i+1], err, x.value)
+		}
+
+		v = v[i+1:]
+
+		ret[name] = append(ret[name], val)
+	}
+
+	return ret, nil
+}
+
+func (x *multiTag) Parse() error {
+	vals, err := x.scan()
+	x.cache = vals
+
+	return err
+}
+
+func (x *multiTag) cached() map[string][]string {
+	if x.cache == nil {
+		cache, _ := x.scan()
+
+		if cache == nil {
+			cache = make(map[string][]string)
+		}
+
+		x.cache = cache
+	}
+
+	return x.cache
+}
+
+func (x *multiTag) Get(key string) string {
+	c := x.cached()
+
+	if v, ok := c[key]; ok {
+		return v[len(v)-1]
+	}
+
+	return ""
+}
+
+func (x *multiTag) GetMany(key string) []string {
+	c := x.cached()
+	return c[key]
+}
+
+func (x *multiTag) Set(key string, value string) {
+	c := x.cached()
+	c[key] = []string{value}
+}
+
+func (x *multiTag) SetMany(key string, value []string) {
+	c := x.cached()
+	c[key] = value
+}
diff --git a/vendor/github.com/jessevdk/go-flags/option.go b/vendor/github.com/jessevdk/go-flags/option.go
new file mode 100644
index 0000000..5f85250
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/option.go
@@ -0,0 +1,459 @@
+package flags
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"reflect"
+	"strings"
+	"unicode/utf8"
+)
+
+// Option flag information. Contains a description of the option, short and
+// long name as well as a default value and whether an argument for this
+// flag is optional.
+type Option struct {
+	// The description of the option flag. This description is shown
+	// automatically in the built-in help.
+	Description string
+
+	// The short name of the option (a single character). If not 0, the
+	// option flag can be 'activated' using -<ShortName>. Either ShortName
+	// or LongName needs to be non-empty.
+	ShortName rune
+
+	// The long name of the option. If not "", the option flag can be
+	// activated using --<LongName>. Either ShortName or LongName needs
+	// to be non-empty.
+	LongName string
+
+	// The default value of the option.
+	Default []string
+
+	// The optional environment default value key name.
+	EnvDefaultKey string
+
+	// The optional delimiter string for EnvDefaultKey values.
+	EnvDefaultDelim string
+
+	// If true, specifies that the argument to an option flag is optional.
+	// When no argument to the flag is specified on the command line, the
+	// value of OptionalValue will be set in the field this option represents.
+	// This is only valid for non-boolean options.
+	OptionalArgument bool
+
+	// The optional value of the option. The optional value is used when
+	// the option flag is marked as having an OptionalArgument. This means
+	// that when the flag is specified, but no option argument is given,
+	// the value of the field this option represents will be set to
+	// OptionalValue. This is only valid for non-boolean options.
+	OptionalValue []string
+
+	// If true, the option _must_ be specified on the command line. If the
+	// option is not specified, the parser will generate an ErrRequired type
+	// error.
+	Required bool
+
+	// A name for the value of an option shown in the Help as --flag [ValueName]
+	ValueName string
+
+	// A mask value to show in the help instead of the default value. This
+	// is useful for hiding sensitive information in the help, such as
+	// passwords.
+	DefaultMask string
+
+	// If non empty, only a certain set of values is allowed for an option.
+	Choices []string
+
+	// If true, the option is not displayed in the help or man page
+	Hidden bool
+
+	// The group which the option belongs to
+	group *Group
+
+	// The struct field which the option represents.
+	field reflect.StructField
+
+	// The struct field value which the option represents.
+	value reflect.Value
+
+	// Determines if the option will be always quoted in the INI output
+	iniQuote bool
+
+	tag            multiTag
+	isSet          bool
+	isSetDefault   bool
+	preventDefault bool
+
+	defaultLiteral string
+}
+
+// LongNameWithNamespace returns the option's long name with the group namespaces
+// prepended by walking up the option's group tree. Namespaces and the long name
+// itself are separated by the parser's namespace delimiter. If the long name is
+// empty an empty string is returned.
+func (option *Option) LongNameWithNamespace() string {
+	if len(option.LongName) == 0 {
+		return ""
+	}
+
+	// fetch the namespace delimiter from the parser which is always at the
+	// end of the group hierarchy
+	namespaceDelimiter := ""
+	g := option.group
+
+	for {
+		if p, ok := g.parent.(*Parser); ok {
+			namespaceDelimiter = p.NamespaceDelimiter
+
+			break
+		}
+
+		switch i := g.parent.(type) {
+		case *Command:
+			g = i.Group
+		case *Group:
+			g = i
+		}
+	}
+
+	// concatenate long name with namespace
+	longName := option.LongName
+	g = option.group
+
+	for g != nil {
+		if g.Namespace != "" {
+			longName = g.Namespace + namespaceDelimiter + longName
+		}
+
+		switch i := g.parent.(type) {
+		case *Command:
+			g = i.Group
+		case *Group:
+			g = i
+		case *Parser:
+			g = nil
+		}
+	}
+
+	return longName
+}
+
+// String converts an option to a human friendly readable string describing the
+// option.
+func (option *Option) String() string {
+	var s string
+	var short string
+
+	if option.ShortName != 0 {
+		data := make([]byte, utf8.RuneLen(option.ShortName))
+		utf8.EncodeRune(data, option.ShortName)
+		short = string(data)
+
+		if len(option.LongName) != 0 {
+			s = fmt.Sprintf("%s%s, %s%s",
+				string(defaultShortOptDelimiter), short,
+				defaultLongOptDelimiter, option.LongNameWithNamespace())
+		} else {
+			s = fmt.Sprintf("%s%s", string(defaultShortOptDelimiter), short)
+		}
+	} else if len(option.LongName) != 0 {
+		s = fmt.Sprintf("%s%s", defaultLongOptDelimiter, option.LongNameWithNamespace())
+	}
+
+	return s
+}
+
+// Value returns the option value as an interface{}.
+func (option *Option) Value() interface{} {
+	return option.value.Interface()
+}
+
+// Field returns the reflect struct field of the option.
+func (option *Option) Field() reflect.StructField {
+	return option.field
+}
+
+// IsSet returns true if option has been set
+func (option *Option) IsSet() bool {
+	return option.isSet
+}
+
+// IsSetDefault returns true if option has been set via the default option tag
+func (option *Option) IsSetDefault() bool {
+	return option.isSetDefault
+}
+
+// Set the value of an option to the specified value. An error will be returned
+// if the specified value could not be converted to the corresponding option
+// value type.
+func (option *Option) set(value *string) error {
+	kind := option.value.Type().Kind()
+
+	if (kind == reflect.Map || kind == reflect.Slice) && !option.isSet {
+		option.empty()
+	}
+
+	option.isSet = true
+	option.preventDefault = true
+
+	if len(option.Choices) != 0 {
+		found := false
+
+		for _, choice := range option.Choices {
+			if choice == *value {
+				found = true
+				break
+			}
+		}
+
+		if !found {
+			allowed := strings.Join(option.Choices[0:len(option.Choices)-1], ", ")
+
+			if len(option.Choices) > 1 {
+				allowed += " or " + option.Choices[len(option.Choices)-1]
+			}
+
+			return newErrorf(ErrInvalidChoice,
+				"Invalid value `%s' for option `%s'. Allowed values are: %s",
+				*value, option, allowed)
+		}
+	}
+
+	if option.isFunc() {
+		return option.call(value)
+	} else if value != nil {
+		return convert(*value, option.value, option.tag)
+	}
+
+	return convert("", option.value, option.tag)
+}
+
+func (option *Option) canCli() bool {
+	return option.ShortName != 0 || len(option.LongName) != 0
+}
+
+func (option *Option) canArgument() bool {
+	if u := option.isUnmarshaler(); u != nil {
+		return true
+	}
+
+	return !option.isBool()
+}
+
+func (option *Option) emptyValue() reflect.Value {
+	tp := option.value.Type()
+
+	if tp.Kind() == reflect.Map {
+		return reflect.MakeMap(tp)
+	}
+
+	return reflect.Zero(tp)
+}
+
+func (option *Option) empty() {
+	if !option.isFunc() {
+		option.value.Set(option.emptyValue())
+	}
+}
+
+func (option *Option) clearDefault() {
+	usedDefault := option.Default
+
+	if envKey := option.EnvDefaultKey; envKey != "" {
+		if value, ok := os.LookupEnv(envKey); ok {
+			if option.EnvDefaultDelim != "" {
+				usedDefault = strings.Split(value,
+					option.EnvDefaultDelim)
+			} else {
+				usedDefault = []string{value}
+			}
+		}
+	}
+
+	option.isSetDefault = true
+
+	if len(usedDefault) > 0 {
+		option.empty()
+
+		for _, d := range usedDefault {
+			option.set(&d)
+			option.isSetDefault = true
+		}
+	} else {
+		tp := option.value.Type()
+
+		switch tp.Kind() {
+		case reflect.Map:
+			if option.value.IsNil() {
+				option.empty()
+			}
+		case reflect.Slice:
+			if option.value.IsNil() {
+				option.empty()
+			}
+		}
+	}
+}
+
+func (option *Option) valueIsDefault() bool {
+	// Check if the value of the option corresponds to its
+	// default value
+	emptyval := option.emptyValue()
+
+	checkvalptr := reflect.New(emptyval.Type())
+	checkval := reflect.Indirect(checkvalptr)
+
+	checkval.Set(emptyval)
+
+	if len(option.Default) != 0 {
+		for _, v := range option.Default {
+			convert(v, checkval, option.tag)
+		}
+	}
+
+	return reflect.DeepEqual(option.value.Interface(), checkval.Interface())
+}
+
+func (option *Option) isUnmarshaler() Unmarshaler {
+	v := option.value
+
+	for {
+		if !v.CanInterface() {
+			break
+		}
+
+		i := v.Interface()
+
+		if u, ok := i.(Unmarshaler); ok {
+			return u
+		}
+
+		if !v.CanAddr() {
+			break
+		}
+
+		v = v.Addr()
+	}
+
+	return nil
+}
+
+func (option *Option) isBool() bool {
+	tp := option.value.Type()
+
+	for {
+		switch tp.Kind() {
+		case reflect.Slice, reflect.Ptr:
+			tp = tp.Elem()
+		case reflect.Bool:
+			return true
+		case reflect.Func:
+			return tp.NumIn() == 0
+		default:
+			return false
+		}
+	}
+}
+
+func (option *Option) isSignedNumber() bool {
+	tp := option.value.Type()
+
+	for {
+		switch tp.Kind() {
+		case reflect.Slice, reflect.Ptr:
+			tp = tp.Elem()
+		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Float32, reflect.Float64:
+			return true
+		default:
+			return false
+		}
+	}
+}
+
+func (option *Option) isFunc() bool {
+	return option.value.Type().Kind() == reflect.Func
+}
+
+func (option *Option) call(value *string) error {
+	var retval []reflect.Value
+
+	if value == nil {
+		retval = option.value.Call(nil)
+	} else {
+		tp := option.value.Type().In(0)
+
+		val := reflect.New(tp)
+		val = reflect.Indirect(val)
+
+		if err := convert(*value, val, option.tag); err != nil {
+			return err
+		}
+
+		retval = option.value.Call([]reflect.Value{val})
+	}
+
+	if len(retval) == 1 && retval[0].Type() == reflect.TypeOf((*error)(nil)).Elem() {
+		if retval[0].Interface() == nil {
+			return nil
+		}
+
+		return retval[0].Interface().(error)
+	}
+
+	return nil
+}
+
+func (option *Option) updateDefaultLiteral() {
+	defs := option.Default
+	def := ""
+
+	if len(defs) == 0 && option.canArgument() {
+		var showdef bool
+
+		switch option.field.Type.Kind() {
+		case reflect.Func, reflect.Ptr:
+			showdef = !option.value.IsNil()
+		case reflect.Slice, reflect.String, reflect.Array:
+			showdef = option.value.Len() > 0
+		case reflect.Map:
+			showdef = !option.value.IsNil() && option.value.Len() > 0
+		default:
+			zeroval := reflect.Zero(option.field.Type)
+			showdef = !reflect.DeepEqual(zeroval.Interface(), option.value.Interface())
+		}
+
+		if showdef {
+			def, _ = convertToString(option.value, option.tag)
+		}
+	} else if len(defs) != 0 {
+		l := len(defs) - 1
+
+		for i := 0; i < l; i++ {
+			def += quoteIfNeeded(defs[i]) + ", "
+		}
+
+		def += quoteIfNeeded(defs[l])
+	}
+
+	option.defaultLiteral = def
+}
+
+func (option *Option) shortAndLongName() string {
+	ret := &bytes.Buffer{}
+
+	if option.ShortName != 0 {
+		ret.WriteRune(defaultShortOptDelimiter)
+		ret.WriteRune(option.ShortName)
+	}
+
+	if len(option.LongName) != 0 {
+		if option.ShortName != 0 {
+			ret.WriteRune('/')
+		}
+
+		ret.WriteString(option.LongName)
+	}
+
+	return ret.String()
+}
diff --git a/vendor/github.com/jessevdk/go-flags/optstyle_other.go b/vendor/github.com/jessevdk/go-flags/optstyle_other.go
new file mode 100644
index 0000000..56dfdae
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/optstyle_other.go
@@ -0,0 +1,67 @@
+// +build !windows forceposix
+
+package flags
+
+import (
+	"strings"
+)
+
+const (
+	defaultShortOptDelimiter = '-'
+	defaultLongOptDelimiter  = "--"
+	defaultNameArgDelimiter  = '='
+)
+
+func argumentStartsOption(arg string) bool {
+	return len(arg) > 0 && arg[0] == '-'
+}
+
+func argumentIsOption(arg string) bool {
+	if len(arg) > 1 && arg[0] == '-' && arg[1] != '-' {
+		return true
+	}
+
+	if len(arg) > 2 && arg[0] == '-' && arg[1] == '-' && arg[2] != '-' {
+		return true
+	}
+
+	return false
+}
+
+// stripOptionPrefix returns the option without the prefix and whether or
+// not the option is a long option or not.
+func stripOptionPrefix(optname string) (prefix string, name string, islong bool) {
+	if strings.HasPrefix(optname, "--") {
+		return "--", optname[2:], true
+	} else if strings.HasPrefix(optname, "-") {
+		return "-", optname[1:], false
+	}
+
+	return "", optname, false
+}
+
+// splitOption attempts to split the passed option into a name and an argument.
+// When there is no argument specified, nil will be returned for it.
+func splitOption(prefix string, option string, islong bool) (string, string, *string) {
+	pos := strings.Index(option, "=")
+
+	if (islong && pos >= 0) || (!islong && pos == 1) {
+		rest := option[pos+1:]
+		return option[:pos], "=", &rest
+	}
+
+	return option, "", nil
+}
+
+// addHelpGroup adds a new group that contains default help parameters.
+func (c *Command) addHelpGroup(showHelp func() error) *Group {
+	var help struct {
+		ShowHelp func() error `short:"h" long:"help" description:"Show this help message"`
+	}
+
+	help.ShowHelp = showHelp
+	ret, _ := c.AddGroup("Help Options", "", &help)
+	ret.isBuiltinHelp = true
+
+	return ret
+}
diff --git a/vendor/github.com/jessevdk/go-flags/optstyle_windows.go b/vendor/github.com/jessevdk/go-flags/optstyle_windows.go
new file mode 100644
index 0000000..f3f28ae
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/optstyle_windows.go
@@ -0,0 +1,108 @@
+// +build !forceposix
+
+package flags
+
+import (
+	"strings"
+)
+
+// Windows uses a front slash for both short and long options.  Also it uses
+// a colon for name/argument delimter.
+const (
+	defaultShortOptDelimiter = '/'
+	defaultLongOptDelimiter  = "/"
+	defaultNameArgDelimiter  = ':'
+)
+
+func argumentStartsOption(arg string) bool {
+	return len(arg) > 0 && (arg[0] == '-' || arg[0] == '/')
+}
+
+func argumentIsOption(arg string) bool {
+	// Windows-style options allow front slash for the option
+	// delimiter.
+	if len(arg) > 1 && arg[0] == '/' {
+		return true
+	}
+
+	if len(arg) > 1 && arg[0] == '-' && arg[1] != '-' {
+		return true
+	}
+
+	if len(arg) > 2 && arg[0] == '-' && arg[1] == '-' && arg[2] != '-' {
+		return true
+	}
+
+	return false
+}
+
+// stripOptionPrefix returns the option without the prefix and whether or
+// not the option is a long option or not.
+func stripOptionPrefix(optname string) (prefix string, name string, islong bool) {
+	// Determine if the argument is a long option or not.  Windows
+	// typically supports both long and short options with a single
+	// front slash as the option delimiter, so handle this situation
+	// nicely.
+	possplit := 0
+
+	if strings.HasPrefix(optname, "--") {
+		possplit = 2
+		islong = true
+	} else if strings.HasPrefix(optname, "-") {
+		possplit = 1
+		islong = false
+	} else if strings.HasPrefix(optname, "/") {
+		possplit = 1
+		islong = len(optname) > 2
+	}
+
+	return optname[:possplit], optname[possplit:], islong
+}
+
+// splitOption attempts to split the passed option into a name and an argument.
+// When there is no argument specified, nil will be returned for it.
+func splitOption(prefix string, option string, islong bool) (string, string, *string) {
+	if len(option) == 0 {
+		return option, "", nil
+	}
+
+	// Windows typically uses a colon for the option name and argument
+	// delimiter while POSIX typically uses an equals.  Support both styles,
+	// but don't allow the two to be mixed.  That is to say /foo:bar and
+	// --foo=bar are acceptable, but /foo=bar and --foo:bar are not.
+	var pos int
+	var sp string
+
+	if prefix == "/" {
+		sp = ":"
+		pos = strings.Index(option, sp)
+	} else if len(prefix) > 0 {
+		sp = "="
+		pos = strings.Index(option, sp)
+	}
+
+	if (islong && pos >= 0) || (!islong && pos == 1) {
+		rest := option[pos+1:]
+		return option[:pos], sp, &rest
+	}
+
+	return option, "", nil
+}
+
+// addHelpGroup adds a new group that contains default help parameters.
+func (c *Command) addHelpGroup(showHelp func() error) *Group {
+	// Windows CLI applications typically use /? for help, so make both
+	// that available as well as the POSIX style h and help.
+	var help struct {
+		ShowHelpWindows func() error `short:"?" description:"Show this help message"`
+		ShowHelpPosix   func() error `short:"h" long:"help" description:"Show this help message"`
+	}
+
+	help.ShowHelpWindows = showHelp
+	help.ShowHelpPosix = showHelp
+
+	ret, _ := c.AddGroup("Help Options", "", &help)
+	ret.isBuiltinHelp = true
+
+	return ret
+}
diff --git a/vendor/github.com/jessevdk/go-flags/parser.go b/vendor/github.com/jessevdk/go-flags/parser.go
new file mode 100644
index 0000000..0a7922a
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/parser.go
@@ -0,0 +1,700 @@
+// Copyright 2012 Jesse van den Kieboom. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flags
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"path"
+	"sort"
+	"strings"
+	"unicode/utf8"
+)
+
+// A Parser provides command line option parsing. It can contain several
+// option groups each with their own set of options.
+type Parser struct {
+	// Embedded, see Command for more information
+	*Command
+
+	// A usage string to be displayed in the help message.
+	Usage string
+
+	// Option flags changing the behavior of the parser.
+	Options Options
+
+	// NamespaceDelimiter separates group namespaces and option long names
+	NamespaceDelimiter string
+
+	// UnknownOptionsHandler is a function which gets called when the parser
+	// encounters an unknown option. The function receives the unknown option
+	// name, a SplitArgument which specifies its value if set with an argument
+	// separator, and the remaining command line arguments.
+	// It should return a new list of remaining arguments to continue parsing,
+	// or an error to indicate a parse failure.
+	UnknownOptionHandler func(option string, arg SplitArgument, args []string) ([]string, error)
+
+	// CompletionHandler is a function gets called to handle the completion of
+	// items. By default, the items are printed and the application is exited.
+	// You can override this default behavior by specifying a custom CompletionHandler.
+	CompletionHandler func(items []Completion)
+
+	// CommandHandler is a function that gets called to handle execution of a
+	// command. By default, the command will simply be executed. This can be
+	// overridden to perform certain actions (such as applying global flags)
+	// just before the command is executed. Note that if you override the
+	// handler it is your responsibility to call the command.Execute function.
+	//
+	// The command passed into CommandHandler may be nil in case there is no
+	// command to be executed when parsing has finished.
+	CommandHandler func(command Commander, args []string) error
+
+	internalError error
+}
+
+// SplitArgument represents the argument value of an option that was passed using
+// an argument separator.
+type SplitArgument interface {
+	// String returns the option's value as a string, and a boolean indicating
+	// if the option was present.
+	Value() (string, bool)
+}
+
+type strArgument struct {
+	value *string
+}
+
+func (s strArgument) Value() (string, bool) {
+	if s.value == nil {
+		return "", false
+	}
+
+	return *s.value, true
+}
+
+// Options provides parser options that change the behavior of the option
+// parser.
+type Options uint
+
+const (
+	// None indicates no options.
+	None Options = 0
+
+	// HelpFlag adds a default Help Options group to the parser containing
+	// -h and --help options. When either -h or --help is specified on the
+	// command line, the parser will return the special error of type
+	// ErrHelp. When PrintErrors is also specified, then the help message
+	// will also be automatically printed to os.Stdout.
+	HelpFlag = 1 << iota
+
+	// PassDoubleDash passes all arguments after a double dash, --, as
+	// remaining command line arguments (i.e. they will not be parsed for
+	// flags).
+	PassDoubleDash
+
+	// IgnoreUnknown ignores any unknown options and passes them as
+	// remaining command line arguments instead of generating an error.
+	IgnoreUnknown
+
+	// PrintErrors prints any errors which occurred during parsing to
+	// os.Stderr. In the special case of ErrHelp, the message will be printed
+	// to os.Stdout.
+	PrintErrors
+
+	// PassAfterNonOption passes all arguments after the first non option
+	// as remaining command line arguments. This is equivalent to strict
+	// POSIX processing.
+	PassAfterNonOption
+
+	// Default is a convenient default set of options which should cover
+	// most of the uses of the flags package.
+	Default = HelpFlag | PrintErrors | PassDoubleDash
+)
+
+type parseState struct {
+	arg        string
+	args       []string
+	retargs    []string
+	positional []*Arg
+	err        error
+
+	command *Command
+	lookup  lookup
+}
+
+// Parse is a convenience function to parse command line options with default
+// settings. The provided data is a pointer to a struct representing the
+// default option group (named "Application Options"). For more control, use
+// flags.NewParser.
+func Parse(data interface{}) ([]string, error) {
+	return NewParser(data, Default).Parse()
+}
+
+// ParseArgs is a convenience function to parse command line options with default
+// settings. The provided data is a pointer to a struct representing the
+// default option group (named "Application Options"). The args argument is
+// the list of command line arguments to parse. If you just want to parse the
+// default program command line arguments (i.e. os.Args), then use flags.Parse
+// instead. For more control, use flags.NewParser.
+func ParseArgs(data interface{}, args []string) ([]string, error) {
+	return NewParser(data, Default).ParseArgs(args)
+}
+
+// NewParser creates a new parser. It uses os.Args[0] as the application
+// name and then calls Parser.NewNamedParser (see Parser.NewNamedParser for
+// more details). The provided data is a pointer to a struct representing the
+// default option group (named "Application Options"), or nil if the default
+// group should not be added. The options parameter specifies a set of options
+// for the parser.
+func NewParser(data interface{}, options Options) *Parser {
+	p := NewNamedParser(path.Base(os.Args[0]), options)
+
+	if data != nil {
+		g, err := p.AddGroup("Application Options", "", data)
+
+		if err == nil {
+			g.parent = p
+		}
+
+		p.internalError = err
+	}
+
+	return p
+}
+
+// NewNamedParser creates a new parser. The appname is used to display the
+// executable name in the built-in help message. Option groups and commands can
+// be added to this parser by using AddGroup and AddCommand.
+func NewNamedParser(appname string, options Options) *Parser {
+	p := &Parser{
+		Command:            newCommand(appname, "", "", nil),
+		Options:            options,
+		NamespaceDelimiter: ".",
+	}
+
+	p.Command.parent = p
+
+	return p
+}
+
+// Parse parses the command line arguments from os.Args using Parser.ParseArgs.
+// For more detailed information see ParseArgs.
+func (p *Parser) Parse() ([]string, error) {
+	return p.ParseArgs(os.Args[1:])
+}
+
+// ParseArgs parses the command line arguments according to the option groups that
+// were added to the parser. On successful parsing of the arguments, the
+// remaining, non-option, arguments (if any) are returned. The returned error
+// indicates a parsing error and can be used with PrintError to display
+// contextual information on where the error occurred exactly.
+//
+// When the common help group has been added (AddHelp) and either -h or --help
+// was specified in the command line arguments, a help message will be
+// automatically printed if the PrintErrors option is enabled.
+// Furthermore, the special error type ErrHelp is returned.
+// It is up to the caller to exit the program if so desired.
+func (p *Parser) ParseArgs(args []string) ([]string, error) {
+	if p.internalError != nil {
+		return nil, p.internalError
+	}
+
+	p.eachOption(func(c *Command, g *Group, option *Option) {
+		option.isSet = false
+		option.isSetDefault = false
+		option.updateDefaultLiteral()
+	})
+
+	// Add built-in help group to all commands if necessary
+	if (p.Options & HelpFlag) != None {
+		p.addHelpGroups(p.showBuiltinHelp)
+	}
+
+	compval := os.Getenv("GO_FLAGS_COMPLETION")
+
+	if len(compval) != 0 {
+		comp := &completion{parser: p}
+		items := comp.complete(args)
+
+		if p.CompletionHandler != nil {
+			p.CompletionHandler(items)
+		} else {
+			comp.print(items, compval == "verbose")
+			os.Exit(0)
+		}
+
+		return nil, nil
+	}
+
+	s := &parseState{
+		args:    args,
+		retargs: make([]string, 0, len(args)),
+	}
+
+	p.fillParseState(s)
+
+	for !s.eof() {
+		arg := s.pop()
+
+		// When PassDoubleDash is set and we encounter a --, then
+		// simply append all the rest as arguments and break out
+		if (p.Options&PassDoubleDash) != None && arg == "--" {
+			s.addArgs(s.args...)
+			break
+		}
+
+		if !argumentIsOption(arg) {
+			// Note: this also sets s.err, so we can just check for
+			// nil here and use s.err later
+			if p.parseNonOption(s) != nil {
+				break
+			}
+
+			continue
+		}
+
+		var err error
+
+		prefix, optname, islong := stripOptionPrefix(arg)
+		optname, _, argument := splitOption(prefix, optname, islong)
+
+		if islong {
+			err = p.parseLong(s, optname, argument)
+		} else {
+			err = p.parseShort(s, optname, argument)
+		}
+
+		if err != nil {
+			ignoreUnknown := (p.Options & IgnoreUnknown) != None
+			parseErr := wrapError(err)
+
+			if parseErr.Type != ErrUnknownFlag || (!ignoreUnknown && p.UnknownOptionHandler == nil) {
+				s.err = parseErr
+				break
+			}
+
+			if ignoreUnknown {
+				s.addArgs(arg)
+			} else if p.UnknownOptionHandler != nil {
+				modifiedArgs, err := p.UnknownOptionHandler(optname, strArgument{argument}, s.args)
+
+				if err != nil {
+					s.err = err
+					break
+				}
+
+				s.args = modifiedArgs
+			}
+		}
+	}
+
+	if s.err == nil {
+		p.eachOption(func(c *Command, g *Group, option *Option) {
+			if option.preventDefault {
+				return
+			}
+
+			option.clearDefault()
+		})
+
+		s.checkRequired(p)
+	}
+
+	var reterr error
+
+	if s.err != nil {
+		reterr = s.err
+	} else if len(s.command.commands) != 0 && !s.command.SubcommandsOptional {
+		reterr = s.estimateCommand()
+	} else if cmd, ok := s.command.data.(Commander); ok {
+		if p.CommandHandler != nil {
+			reterr = p.CommandHandler(cmd, s.retargs)
+		} else {
+			reterr = cmd.Execute(s.retargs)
+		}
+	} else if p.CommandHandler != nil {
+		reterr = p.CommandHandler(nil, s.retargs)
+	}
+
+	if reterr != nil {
+		var retargs []string
+
+		if ourErr, ok := reterr.(*Error); !ok || ourErr.Type != ErrHelp {
+			retargs = append([]string{s.arg}, s.args...)
+		} else {
+			retargs = s.args
+		}
+
+		return retargs, p.printError(reterr)
+	}
+
+	return s.retargs, nil
+}
+
+func (p *parseState) eof() bool {
+	return len(p.args) == 0
+}
+
+func (p *parseState) pop() string {
+	if p.eof() {
+		return ""
+	}
+
+	p.arg = p.args[0]
+	p.args = p.args[1:]
+
+	return p.arg
+}
+
+func (p *parseState) peek() string {
+	if p.eof() {
+		return ""
+	}
+
+	return p.args[0]
+}
+
+func (p *parseState) checkRequired(parser *Parser) error {
+	c := parser.Command
+
+	var required []*Option
+
+	for c != nil {
+		c.eachGroup(func(g *Group) {
+			for _, option := range g.options {
+				if !option.isSet && option.Required {
+					required = append(required, option)
+				}
+			}
+		})
+
+		c = c.Active
+	}
+
+	if len(required) == 0 {
+		if len(p.positional) > 0 {
+			var reqnames []string
+
+			for _, arg := range p.positional {
+				argRequired := (!arg.isRemaining() && p.command.ArgsRequired) || arg.Required != -1 || arg.RequiredMaximum != -1
+
+				if !argRequired {
+					continue
+				}
+
+				if arg.isRemaining() {
+					if arg.value.Len() < arg.Required {
+						var arguments string
+
+						if arg.Required > 1 {
+							arguments = "arguments, but got only " + fmt.Sprintf("%d", arg.value.Len())
+						} else {
+							arguments = "argument"
+						}
+
+						reqnames = append(reqnames, "`"+arg.Name+" (at least "+fmt.Sprintf("%d", arg.Required)+" "+arguments+")`")
+					} else if arg.RequiredMaximum != -1 && arg.value.Len() > arg.RequiredMaximum {
+						if arg.RequiredMaximum == 0 {
+							reqnames = append(reqnames, "`"+arg.Name+" (zero arguments)`")
+						} else {
+							var arguments string
+
+							if arg.RequiredMaximum > 1 {
+								arguments = "arguments, but got " + fmt.Sprintf("%d", arg.value.Len())
+							} else {
+								arguments = "argument"
+							}
+
+							reqnames = append(reqnames, "`"+arg.Name+" (at most "+fmt.Sprintf("%d", arg.RequiredMaximum)+" "+arguments+")`")
+						}
+					}
+				} else {
+					reqnames = append(reqnames, "`"+arg.Name+"`")
+				}
+			}
+
+			if len(reqnames) == 0 {
+				return nil
+			}
+
+			var msg string
+
+			if len(reqnames) == 1 {
+				msg = fmt.Sprintf("the required argument %s was not provided", reqnames[0])
+			} else {
+				msg = fmt.Sprintf("the required arguments %s and %s were not provided",
+					strings.Join(reqnames[:len(reqnames)-1], ", "), reqnames[len(reqnames)-1])
+			}
+
+			p.err = newError(ErrRequired, msg)
+			return p.err
+		}
+
+		return nil
+	}
+
+	names := make([]string, 0, len(required))
+
+	for _, k := range required {
+		names = append(names, "`"+k.String()+"'")
+	}
+
+	sort.Strings(names)
+
+	var msg string
+
+	if len(names) == 1 {
+		msg = fmt.Sprintf("the required flag %s was not specified", names[0])
+	} else {
+		msg = fmt.Sprintf("the required flags %s and %s were not specified",
+			strings.Join(names[:len(names)-1], ", "), names[len(names)-1])
+	}
+
+	p.err = newError(ErrRequired, msg)
+	return p.err
+}
+
+func (p *parseState) estimateCommand() error {
+	commands := p.command.sortedVisibleCommands()
+	cmdnames := make([]string, len(commands))
+
+	for i, v := range commands {
+		cmdnames[i] = v.Name
+	}
+
+	var msg string
+	var errtype ErrorType
+
+	if len(p.retargs) != 0 {
+		c, l := closestChoice(p.retargs[0], cmdnames)
+		msg = fmt.Sprintf("Unknown command `%s'", p.retargs[0])
+		errtype = ErrUnknownCommand
+
+		if float32(l)/float32(len(c)) < 0.5 {
+			msg = fmt.Sprintf("%s, did you mean `%s'?", msg, c)
+		} else if len(cmdnames) == 1 {
+			msg = fmt.Sprintf("%s. You should use the %s command",
+				msg,
+				cmdnames[0])
+		} else if len(cmdnames) > 1 {
+			msg = fmt.Sprintf("%s. Please specify one command of: %s or %s",
+				msg,
+				strings.Join(cmdnames[:len(cmdnames)-1], ", "),
+				cmdnames[len(cmdnames)-1])
+		}
+	} else {
+		errtype = ErrCommandRequired
+
+		if len(cmdnames) == 1 {
+			msg = fmt.Sprintf("Please specify the %s command", cmdnames[0])
+		} else if len(cmdnames) > 1 {
+			msg = fmt.Sprintf("Please specify one command of: %s or %s",
+				strings.Join(cmdnames[:len(cmdnames)-1], ", "),
+				cmdnames[len(cmdnames)-1])
+		}
+	}
+
+	return newError(errtype, msg)
+}
+
+func (p *Parser) parseOption(s *parseState, name string, option *Option, canarg bool, argument *string) (err error) {
+	if !option.canArgument() {
+		if argument != nil {
+			return newErrorf(ErrNoArgumentForBool, "bool flag `%s' cannot have an argument", option)
+		}
+
+		err = option.set(nil)
+	} else if argument != nil || (canarg && !s.eof()) {
+		var arg string
+
+		if argument != nil {
+			arg = *argument
+		} else {
+			arg = s.pop()
+
+			if argumentIsOption(arg) && !(option.isSignedNumber() && len(arg) > 1 && arg[0] == '-' && arg[1] >= '0' && arg[1] <= '9') {
+				return newErrorf(ErrExpectedArgument, "expected argument for flag `%s', but got option `%s'", option, arg)
+			} else if p.Options&PassDoubleDash != 0 && arg == "--" {
+				return newErrorf(ErrExpectedArgument, "expected argument for flag `%s', but got double dash `--'", option)
+			}
+		}
+
+		if option.tag.Get("unquote") != "false" {
+			arg, err = unquoteIfPossible(arg)
+		}
+
+		if err == nil {
+			err = option.set(&arg)
+		}
+	} else if option.OptionalArgument {
+		option.empty()
+
+		for _, v := range option.OptionalValue {
+			err = option.set(&v)
+
+			if err != nil {
+				break
+			}
+		}
+	} else {
+		err = newErrorf(ErrExpectedArgument, "expected argument for flag `%s'", option)
+	}
+
+	if err != nil {
+		if _, ok := err.(*Error); !ok {
+			err = newErrorf(ErrMarshal, "invalid argument for flag `%s' (expected %s): %s",
+				option,
+				option.value.Type(),
+				err.Error())
+		}
+	}
+
+	return err
+}
+
+func (p *Parser) parseLong(s *parseState, name string, argument *string) error {
+	if option := s.lookup.longNames[name]; option != nil {
+		// Only long options that are required can consume an argument
+		// from the argument list
+		canarg := !option.OptionalArgument
+
+		return p.parseOption(s, name, option, canarg, argument)
+	}
+
+	return newErrorf(ErrUnknownFlag, "unknown flag `%s'", name)
+}
+
+func (p *Parser) splitShortConcatArg(s *parseState, optname string) (string, *string) {
+	c, n := utf8.DecodeRuneInString(optname)
+
+	if n == len(optname) {
+		return optname, nil
+	}
+
+	first := string(c)
+
+	if option := s.lookup.shortNames[first]; option != nil && option.canArgument() {
+		arg := optname[n:]
+		return first, &arg
+	}
+
+	return optname, nil
+}
+
+func (p *Parser) parseShort(s *parseState, optname string, argument *string) error {
+	if argument == nil {
+		optname, argument = p.splitShortConcatArg(s, optname)
+	}
+
+	for i, c := range optname {
+		shortname := string(c)
+
+		if option := s.lookup.shortNames[shortname]; option != nil {
+			// Only the last short argument can consume an argument from
+			// the arguments list, and only if it's non optional
+			canarg := (i+utf8.RuneLen(c) == len(optname)) && !option.OptionalArgument
+
+			if err := p.parseOption(s, shortname, option, canarg, argument); err != nil {
+				return err
+			}
+		} else {
+			return newErrorf(ErrUnknownFlag, "unknown flag `%s'", shortname)
+		}
+
+		// Only the first option can have a concatted argument, so just
+		// clear argument here
+		argument = nil
+	}
+
+	return nil
+}
+
+func (p *parseState) addArgs(args ...string) error {
+	for len(p.positional) > 0 && len(args) > 0 {
+		arg := p.positional[0]
+
+		if err := convert(args[0], arg.value, arg.tag); err != nil {
+			p.err = err
+			return err
+		}
+
+		if !arg.isRemaining() {
+			p.positional = p.positional[1:]
+		}
+
+		args = args[1:]
+	}
+
+	p.retargs = append(p.retargs, args...)
+	return nil
+}
+
+func (p *Parser) parseNonOption(s *parseState) error {
+	if len(s.positional) > 0 {
+		return s.addArgs(s.arg)
+	}
+
+	if len(s.command.commands) > 0 && len(s.retargs) == 0 {
+		if cmd := s.lookup.commands[s.arg]; cmd != nil {
+			s.command.Active = cmd
+			cmd.fillParseState(s)
+
+			return nil
+		} else if !s.command.SubcommandsOptional {
+			s.addArgs(s.arg)
+			return newErrorf(ErrUnknownCommand, "Unknown command `%s'", s.arg)
+		}
+	}
+
+	if (p.Options & PassAfterNonOption) != None {
+		// If PassAfterNonOption is set then all remaining arguments
+		// are considered positional
+		if err := s.addArgs(s.arg); err != nil {
+			return err
+		}
+
+		if err := s.addArgs(s.args...); err != nil {
+			return err
+		}
+
+		s.args = []string{}
+	} else {
+		return s.addArgs(s.arg)
+	}
+
+	return nil
+}
+
+func (p *Parser) showBuiltinHelp() error {
+	var b bytes.Buffer
+
+	p.WriteHelp(&b)
+	return newError(ErrHelp, b.String())
+}
+
+func (p *Parser) printError(err error) error {
+	if err != nil && (p.Options&PrintErrors) != None {
+		flagsErr, ok := err.(*Error)
+
+		if ok && flagsErr.Type == ErrHelp {
+			fmt.Fprintln(os.Stdout, err)
+		} else {
+			fmt.Fprintln(os.Stderr, err)
+		}
+	}
+
+	return err
+}
+
+func (p *Parser) clearIsSet() {
+	p.eachCommand(func(c *Command) {
+		c.eachGroup(func(g *Group) {
+			for _, option := range g.options {
+				option.isSet = false
+			}
+		})
+	}, true)
+}
diff --git a/vendor/github.com/jessevdk/go-flags/termsize.go b/vendor/github.com/jessevdk/go-flags/termsize.go
new file mode 100644
index 0000000..1ca6a85
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/termsize.go
@@ -0,0 +1,28 @@
+// +build !windows,!plan9,!solaris,!appengine
+
+package flags
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+type winsize struct {
+	row, col       uint16
+	xpixel, ypixel uint16
+}
+
+func getTerminalColumns() int {
+	ws := winsize{}
+
+	if tIOCGWINSZ != 0 {
+		syscall.Syscall(syscall.SYS_IOCTL,
+			uintptr(0),
+			uintptr(tIOCGWINSZ),
+			uintptr(unsafe.Pointer(&ws)))
+
+		return int(ws.col)
+	}
+
+	return 80
+}
diff --git a/vendor/github.com/jessevdk/go-flags/termsize_nosysioctl.go b/vendor/github.com/jessevdk/go-flags/termsize_nosysioctl.go
new file mode 100644
index 0000000..3d5385b
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/termsize_nosysioctl.go
@@ -0,0 +1,7 @@
+// +build windows plan9 solaris appengine
+
+package flags
+
+func getTerminalColumns() int {
+	return 80
+}
diff --git a/vendor/github.com/jessevdk/go-flags/tiocgwinsz_bsdish.go b/vendor/github.com/jessevdk/go-flags/tiocgwinsz_bsdish.go
new file mode 100644
index 0000000..fcc1186
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/tiocgwinsz_bsdish.go
@@ -0,0 +1,7 @@
+// +build darwin freebsd netbsd openbsd
+
+package flags
+
+const (
+	tIOCGWINSZ = 0x40087468
+)
diff --git a/vendor/github.com/jessevdk/go-flags/tiocgwinsz_linux.go b/vendor/github.com/jessevdk/go-flags/tiocgwinsz_linux.go
new file mode 100644
index 0000000..e3975e2
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/tiocgwinsz_linux.go
@@ -0,0 +1,7 @@
+// +build linux
+
+package flags
+
+const (
+	tIOCGWINSZ = 0x5413
+)
diff --git a/vendor/github.com/jessevdk/go-flags/tiocgwinsz_other.go b/vendor/github.com/jessevdk/go-flags/tiocgwinsz_other.go
new file mode 100644
index 0000000..3082151
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/tiocgwinsz_other.go
@@ -0,0 +1,7 @@
+// +build !darwin,!freebsd,!netbsd,!openbsd,!linux
+
+package flags
+
+const (
+	tIOCGWINSZ = 0
+)