diff --git a/vendor/go.uber.org/zap/sugar.go b/vendor/go.uber.org/zap/sugar.go
new file mode 100644
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--- /dev/null
+++ b/vendor/go.uber.org/zap/sugar.go
@@ -0,0 +1,315 @@
+// Copyright (c) 2016 Uber Technologies, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package zap
+
+import (
+	"fmt"
+
+	"go.uber.org/zap/zapcore"
+
+	"go.uber.org/multierr"
+)
+
+const (
+	_oddNumberErrMsg    = "Ignored key without a value."
+	_nonStringKeyErrMsg = "Ignored key-value pairs with non-string keys."
+)
+
+// A SugaredLogger wraps the base Logger functionality in a slower, but less
+// verbose, API. Any Logger can be converted to a SugaredLogger with its Sugar
+// method.
+//
+// Unlike the Logger, the SugaredLogger doesn't insist on structured logging.
+// For each log level, it exposes three methods: one for loosely-typed
+// structured logging, one for println-style formatting, and one for
+// printf-style formatting. For example, SugaredLoggers can produce InfoLevel
+// output with Infow ("info with" structured context), Info, or Infof.
+type SugaredLogger struct {
+	base *Logger
+}
+
+// Desugar unwraps a SugaredLogger, exposing the original Logger. Desugaring
+// is quite inexpensive, so it's reasonable for a single application to use
+// both Loggers and SugaredLoggers, converting between them on the boundaries
+// of performance-sensitive code.
+func (s *SugaredLogger) Desugar() *Logger {
+	base := s.base.clone()
+	base.callerSkip -= 2
+	return base
+}
+
+// Named adds a sub-scope to the logger's name. See Logger.Named for details.
+func (s *SugaredLogger) Named(name string) *SugaredLogger {
+	return &SugaredLogger{base: s.base.Named(name)}
+}
+
+// With adds a variadic number of fields to the logging context. It accepts a
+// mix of strongly-typed Field objects and loosely-typed key-value pairs. When
+// processing pairs, the first element of the pair is used as the field key
+// and the second as the field value.
+//
+// For example,
+//   sugaredLogger.With(
+//     "hello", "world",
+//     "failure", errors.New("oh no"),
+//     Stack(),
+//     "count", 42,
+//     "user", User{Name: "alice"},
+//  )
+// is the equivalent of
+//   unsugared.With(
+//     String("hello", "world"),
+//     String("failure", "oh no"),
+//     Stack(),
+//     Int("count", 42),
+//     Object("user", User{Name: "alice"}),
+//   )
+//
+// Note that the keys in key-value pairs should be strings. In development,
+// passing a non-string key panics. In production, the logger is more
+// forgiving: a separate error is logged, but the key-value pair is skipped
+// and execution continues. Passing an orphaned key triggers similar behavior:
+// panics in development and errors in production.
+func (s *SugaredLogger) With(args ...interface{}) *SugaredLogger {
+	return &SugaredLogger{base: s.base.With(s.sweetenFields(args)...)}
+}
+
+// Debug uses fmt.Sprint to construct and log a message.
+func (s *SugaredLogger) Debug(args ...interface{}) {
+	s.log(DebugLevel, "", args, nil)
+}
+
+// Info uses fmt.Sprint to construct and log a message.
+func (s *SugaredLogger) Info(args ...interface{}) {
+	s.log(InfoLevel, "", args, nil)
+}
+
+// Warn uses fmt.Sprint to construct and log a message.
+func (s *SugaredLogger) Warn(args ...interface{}) {
+	s.log(WarnLevel, "", args, nil)
+}
+
+// Error uses fmt.Sprint to construct and log a message.
+func (s *SugaredLogger) Error(args ...interface{}) {
+	s.log(ErrorLevel, "", args, nil)
+}
+
+// DPanic uses fmt.Sprint to construct and log a message. In development, the
+// logger then panics. (See DPanicLevel for details.)
+func (s *SugaredLogger) DPanic(args ...interface{}) {
+	s.log(DPanicLevel, "", args, nil)
+}
+
+// Panic uses fmt.Sprint to construct and log a message, then panics.
+func (s *SugaredLogger) Panic(args ...interface{}) {
+	s.log(PanicLevel, "", args, nil)
+}
+
+// Fatal uses fmt.Sprint to construct and log a message, then calls os.Exit.
+func (s *SugaredLogger) Fatal(args ...interface{}) {
+	s.log(FatalLevel, "", args, nil)
+}
+
+// Debugf uses fmt.Sprintf to log a templated message.
+func (s *SugaredLogger) Debugf(template string, args ...interface{}) {
+	s.log(DebugLevel, template, args, nil)
+}
+
+// Infof uses fmt.Sprintf to log a templated message.
+func (s *SugaredLogger) Infof(template string, args ...interface{}) {
+	s.log(InfoLevel, template, args, nil)
+}
+
+// Warnf uses fmt.Sprintf to log a templated message.
+func (s *SugaredLogger) Warnf(template string, args ...interface{}) {
+	s.log(WarnLevel, template, args, nil)
+}
+
+// Errorf uses fmt.Sprintf to log a templated message.
+func (s *SugaredLogger) Errorf(template string, args ...interface{}) {
+	s.log(ErrorLevel, template, args, nil)
+}
+
+// DPanicf uses fmt.Sprintf to log a templated message. In development, the
+// logger then panics. (See DPanicLevel for details.)
+func (s *SugaredLogger) DPanicf(template string, args ...interface{}) {
+	s.log(DPanicLevel, template, args, nil)
+}
+
+// Panicf uses fmt.Sprintf to log a templated message, then panics.
+func (s *SugaredLogger) Panicf(template string, args ...interface{}) {
+	s.log(PanicLevel, template, args, nil)
+}
+
+// Fatalf uses fmt.Sprintf to log a templated message, then calls os.Exit.
+func (s *SugaredLogger) Fatalf(template string, args ...interface{}) {
+	s.log(FatalLevel, template, args, nil)
+}
+
+// Debugw logs a message with some additional context. The variadic key-value
+// pairs are treated as they are in With.
+//
+// When debug-level logging is disabled, this is much faster than
+//  s.With(keysAndValues).Debug(msg)
+func (s *SugaredLogger) Debugw(msg string, keysAndValues ...interface{}) {
+	s.log(DebugLevel, msg, nil, keysAndValues)
+}
+
+// Infow logs a message with some additional context. The variadic key-value
+// pairs are treated as they are in With.
+func (s *SugaredLogger) Infow(msg string, keysAndValues ...interface{}) {
+	s.log(InfoLevel, msg, nil, keysAndValues)
+}
+
+// Warnw logs a message with some additional context. The variadic key-value
+// pairs are treated as they are in With.
+func (s *SugaredLogger) Warnw(msg string, keysAndValues ...interface{}) {
+	s.log(WarnLevel, msg, nil, keysAndValues)
+}
+
+// Errorw logs a message with some additional context. The variadic key-value
+// pairs are treated as they are in With.
+func (s *SugaredLogger) Errorw(msg string, keysAndValues ...interface{}) {
+	s.log(ErrorLevel, msg, nil, keysAndValues)
+}
+
+// DPanicw logs a message with some additional context. In development, the
+// logger then panics. (See DPanicLevel for details.) The variadic key-value
+// pairs are treated as they are in With.
+func (s *SugaredLogger) DPanicw(msg string, keysAndValues ...interface{}) {
+	s.log(DPanicLevel, msg, nil, keysAndValues)
+}
+
+// Panicw logs a message with some additional context, then panics. The
+// variadic key-value pairs are treated as they are in With.
+func (s *SugaredLogger) Panicw(msg string, keysAndValues ...interface{}) {
+	s.log(PanicLevel, msg, nil, keysAndValues)
+}
+
+// Fatalw logs a message with some additional context, then calls os.Exit. The
+// variadic key-value pairs are treated as they are in With.
+func (s *SugaredLogger) Fatalw(msg string, keysAndValues ...interface{}) {
+	s.log(FatalLevel, msg, nil, keysAndValues)
+}
+
+// Sync flushes any buffered log entries.
+func (s *SugaredLogger) Sync() error {
+	return s.base.Sync()
+}
+
+func (s *SugaredLogger) log(lvl zapcore.Level, template string, fmtArgs []interface{}, context []interface{}) {
+	// If logging at this level is completely disabled, skip the overhead of
+	// string formatting.
+	if lvl < DPanicLevel && !s.base.Core().Enabled(lvl) {
+		return
+	}
+
+	msg := getMessage(template, fmtArgs)
+	if ce := s.base.Check(lvl, msg); ce != nil {
+		ce.Write(s.sweetenFields(context)...)
+	}
+}
+
+// getMessage format with Sprint, Sprintf, or neither.
+func getMessage(template string, fmtArgs []interface{}) string {
+	if len(fmtArgs) == 0 {
+		return template
+	}
+
+	if template != "" {
+		return fmt.Sprintf(template, fmtArgs...)
+	}
+
+	if len(fmtArgs) == 1 {
+		if str, ok := fmtArgs[0].(string); ok {
+			return str
+		}
+	}
+	return fmt.Sprint(fmtArgs...)
+}
+
+func (s *SugaredLogger) sweetenFields(args []interface{}) []Field {
+	if len(args) == 0 {
+		return nil
+	}
+
+	// Allocate enough space for the worst case; if users pass only structured
+	// fields, we shouldn't penalize them with extra allocations.
+	fields := make([]Field, 0, len(args))
+	var invalid invalidPairs
+
+	for i := 0; i < len(args); {
+		// This is a strongly-typed field. Consume it and move on.
+		if f, ok := args[i].(Field); ok {
+			fields = append(fields, f)
+			i++
+			continue
+		}
+
+		// Make sure this element isn't a dangling key.
+		if i == len(args)-1 {
+			s.base.Error(_oddNumberErrMsg, Any("ignored", args[i]))
+			break
+		}
+
+		// Consume this value and the next, treating them as a key-value pair. If the
+		// key isn't a string, add this pair to the slice of invalid pairs.
+		key, val := args[i], args[i+1]
+		if keyStr, ok := key.(string); !ok {
+			// Subsequent errors are likely, so allocate once up front.
+			if cap(invalid) == 0 {
+				invalid = make(invalidPairs, 0, len(args)/2)
+			}
+			invalid = append(invalid, invalidPair{i, key, val})
+		} else {
+			fields = append(fields, Any(keyStr, val))
+		}
+		i += 2
+	}
+
+	// If we encountered any invalid key-value pairs, log an error.
+	if len(invalid) > 0 {
+		s.base.Error(_nonStringKeyErrMsg, Array("invalid", invalid))
+	}
+	return fields
+}
+
+type invalidPair struct {
+	position   int
+	key, value interface{}
+}
+
+func (p invalidPair) MarshalLogObject(enc zapcore.ObjectEncoder) error {
+	enc.AddInt64("position", int64(p.position))
+	Any("key", p.key).AddTo(enc)
+	Any("value", p.value).AddTo(enc)
+	return nil
+}
+
+type invalidPairs []invalidPair
+
+func (ps invalidPairs) MarshalLogArray(enc zapcore.ArrayEncoder) error {
+	var err error
+	for i := range ps {
+		err = multierr.Append(err, enc.AppendObject(ps[i]))
+	}
+	return err
+}