diff --git a/vendor/github.com/gogo/protobuf/protoc-gen-gogo/descriptor/helper.go b/vendor/github.com/gogo/protobuf/protoc-gen-gogo/descriptor/helper.go
new file mode 100644
index 0000000..e0846a3
--- /dev/null
+++ b/vendor/github.com/gogo/protobuf/protoc-gen-gogo/descriptor/helper.go
@@ -0,0 +1,390 @@
+// Protocol Buffers for Go with Gadgets
+//
+// Copyright (c) 2013, The GoGo Authors. All rights reserved.
+// http://github.com/gogo/protobuf
+//
+// 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.
+//
+// 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.
+
+package descriptor
+
+import (
+	"strings"
+)
+
+func (msg *DescriptorProto) GetMapFields() (*FieldDescriptorProto, *FieldDescriptorProto) {
+	if !msg.GetOptions().GetMapEntry() {
+		return nil, nil
+	}
+	return msg.GetField()[0], msg.GetField()[1]
+}
+
+func dotToUnderscore(r rune) rune {
+	if r == '.' {
+		return '_'
+	}
+	return r
+}
+
+func (field *FieldDescriptorProto) WireType() (wire int) {
+	switch *field.Type {
+	case FieldDescriptorProto_TYPE_DOUBLE:
+		return 1
+	case FieldDescriptorProto_TYPE_FLOAT:
+		return 5
+	case FieldDescriptorProto_TYPE_INT64:
+		return 0
+	case FieldDescriptorProto_TYPE_UINT64:
+		return 0
+	case FieldDescriptorProto_TYPE_INT32:
+		return 0
+	case FieldDescriptorProto_TYPE_UINT32:
+		return 0
+	case FieldDescriptorProto_TYPE_FIXED64:
+		return 1
+	case FieldDescriptorProto_TYPE_FIXED32:
+		return 5
+	case FieldDescriptorProto_TYPE_BOOL:
+		return 0
+	case FieldDescriptorProto_TYPE_STRING:
+		return 2
+	case FieldDescriptorProto_TYPE_GROUP:
+		return 2
+	case FieldDescriptorProto_TYPE_MESSAGE:
+		return 2
+	case FieldDescriptorProto_TYPE_BYTES:
+		return 2
+	case FieldDescriptorProto_TYPE_ENUM:
+		return 0
+	case FieldDescriptorProto_TYPE_SFIXED32:
+		return 5
+	case FieldDescriptorProto_TYPE_SFIXED64:
+		return 1
+	case FieldDescriptorProto_TYPE_SINT32:
+		return 0
+	case FieldDescriptorProto_TYPE_SINT64:
+		return 0
+	}
+	panic("unreachable")
+}
+
+func (field *FieldDescriptorProto) GetKeyUint64() (x uint64) {
+	packed := field.IsPacked()
+	wireType := field.WireType()
+	fieldNumber := field.GetNumber()
+	if packed {
+		wireType = 2
+	}
+	x = uint64(uint32(fieldNumber)<<3 | uint32(wireType))
+	return x
+}
+
+func (field *FieldDescriptorProto) GetKey3Uint64() (x uint64) {
+	packed := field.IsPacked3()
+	wireType := field.WireType()
+	fieldNumber := field.GetNumber()
+	if packed {
+		wireType = 2
+	}
+	x = uint64(uint32(fieldNumber)<<3 | uint32(wireType))
+	return x
+}
+
+func (field *FieldDescriptorProto) GetKey() []byte {
+	x := field.GetKeyUint64()
+	i := 0
+	keybuf := make([]byte, 0)
+	for i = 0; x > 127; i++ {
+		keybuf = append(keybuf, 0x80|uint8(x&0x7F))
+		x >>= 7
+	}
+	keybuf = append(keybuf, uint8(x))
+	return keybuf
+}
+
+func (field *FieldDescriptorProto) GetKey3() []byte {
+	x := field.GetKey3Uint64()
+	i := 0
+	keybuf := make([]byte, 0)
+	for i = 0; x > 127; i++ {
+		keybuf = append(keybuf, 0x80|uint8(x&0x7F))
+		x >>= 7
+	}
+	keybuf = append(keybuf, uint8(x))
+	return keybuf
+}
+
+func (desc *FileDescriptorSet) GetField(packageName, messageName, fieldName string) *FieldDescriptorProto {
+	msg := desc.GetMessage(packageName, messageName)
+	if msg == nil {
+		return nil
+	}
+	for _, field := range msg.GetField() {
+		if field.GetName() == fieldName {
+			return field
+		}
+	}
+	return nil
+}
+
+func (file *FileDescriptorProto) GetMessage(typeName string) *DescriptorProto {
+	for _, msg := range file.GetMessageType() {
+		if msg.GetName() == typeName {
+			return msg
+		}
+		nes := file.GetNestedMessage(msg, strings.TrimPrefix(typeName, msg.GetName()+"."))
+		if nes != nil {
+			return nes
+		}
+	}
+	return nil
+}
+
+func (file *FileDescriptorProto) GetNestedMessage(msg *DescriptorProto, typeName string) *DescriptorProto {
+	for _, nes := range msg.GetNestedType() {
+		if nes.GetName() == typeName {
+			return nes
+		}
+		res := file.GetNestedMessage(nes, strings.TrimPrefix(typeName, nes.GetName()+"."))
+		if res != nil {
+			return res
+		}
+	}
+	return nil
+}
+
+func (desc *FileDescriptorSet) GetMessage(packageName string, typeName string) *DescriptorProto {
+	for _, file := range desc.GetFile() {
+		if strings.Map(dotToUnderscore, file.GetPackage()) != strings.Map(dotToUnderscore, packageName) {
+			continue
+		}
+		for _, msg := range file.GetMessageType() {
+			if msg.GetName() == typeName {
+				return msg
+			}
+		}
+		for _, msg := range file.GetMessageType() {
+			for _, nes := range msg.GetNestedType() {
+				if nes.GetName() == typeName {
+					return nes
+				}
+				if msg.GetName()+"."+nes.GetName() == typeName {
+					return nes
+				}
+			}
+		}
+	}
+	return nil
+}
+
+func (desc *FileDescriptorSet) IsProto3(packageName string, typeName string) bool {
+	for _, file := range desc.GetFile() {
+		if strings.Map(dotToUnderscore, file.GetPackage()) != strings.Map(dotToUnderscore, packageName) {
+			continue
+		}
+		for _, msg := range file.GetMessageType() {
+			if msg.GetName() == typeName {
+				return file.GetSyntax() == "proto3"
+			}
+		}
+		for _, msg := range file.GetMessageType() {
+			for _, nes := range msg.GetNestedType() {
+				if nes.GetName() == typeName {
+					return file.GetSyntax() == "proto3"
+				}
+				if msg.GetName()+"."+nes.GetName() == typeName {
+					return file.GetSyntax() == "proto3"
+				}
+			}
+		}
+	}
+	return false
+}
+
+func (msg *DescriptorProto) IsExtendable() bool {
+	return len(msg.GetExtensionRange()) > 0
+}
+
+func (desc *FileDescriptorSet) FindExtension(packageName string, typeName string, fieldName string) (extPackageName string, field *FieldDescriptorProto) {
+	parent := desc.GetMessage(packageName, typeName)
+	if parent == nil {
+		return "", nil
+	}
+	if !parent.IsExtendable() {
+		return "", nil
+	}
+	extendee := "." + packageName + "." + typeName
+	for _, file := range desc.GetFile() {
+		for _, ext := range file.GetExtension() {
+			if strings.Map(dotToUnderscore, file.GetPackage()) == strings.Map(dotToUnderscore, packageName) {
+				if !(ext.GetExtendee() == typeName || ext.GetExtendee() == extendee) {
+					continue
+				}
+			} else {
+				if ext.GetExtendee() != extendee {
+					continue
+				}
+			}
+			if ext.GetName() == fieldName {
+				return file.GetPackage(), ext
+			}
+		}
+	}
+	return "", nil
+}
+
+func (desc *FileDescriptorSet) FindExtensionByFieldNumber(packageName string, typeName string, fieldNum int32) (extPackageName string, field *FieldDescriptorProto) {
+	parent := desc.GetMessage(packageName, typeName)
+	if parent == nil {
+		return "", nil
+	}
+	if !parent.IsExtendable() {
+		return "", nil
+	}
+	extendee := "." + packageName + "." + typeName
+	for _, file := range desc.GetFile() {
+		for _, ext := range file.GetExtension() {
+			if strings.Map(dotToUnderscore, file.GetPackage()) == strings.Map(dotToUnderscore, packageName) {
+				if !(ext.GetExtendee() == typeName || ext.GetExtendee() == extendee) {
+					continue
+				}
+			} else {
+				if ext.GetExtendee() != extendee {
+					continue
+				}
+			}
+			if ext.GetNumber() == fieldNum {
+				return file.GetPackage(), ext
+			}
+		}
+	}
+	return "", nil
+}
+
+func (desc *FileDescriptorSet) FindMessage(packageName string, typeName string, fieldName string) (msgPackageName string, msgName string) {
+	parent := desc.GetMessage(packageName, typeName)
+	if parent == nil {
+		return "", ""
+	}
+	field := parent.GetFieldDescriptor(fieldName)
+	if field == nil {
+		var extPackageName string
+		extPackageName, field = desc.FindExtension(packageName, typeName, fieldName)
+		if field == nil {
+			return "", ""
+		}
+		packageName = extPackageName
+	}
+	typeNames := strings.Split(field.GetTypeName(), ".")
+	if len(typeNames) == 1 {
+		msg := desc.GetMessage(packageName, typeName)
+		if msg == nil {
+			return "", ""
+		}
+		return packageName, msg.GetName()
+	}
+	if len(typeNames) > 2 {
+		for i := 1; i < len(typeNames)-1; i++ {
+			packageName = strings.Join(typeNames[1:len(typeNames)-i], ".")
+			typeName = strings.Join(typeNames[len(typeNames)-i:], ".")
+			msg := desc.GetMessage(packageName, typeName)
+			if msg != nil {
+				typeNames := strings.Split(msg.GetName(), ".")
+				if len(typeNames) == 1 {
+					return packageName, msg.GetName()
+				}
+				return strings.Join(typeNames[1:len(typeNames)-1], "."), typeNames[len(typeNames)-1]
+			}
+		}
+	}
+	return "", ""
+}
+
+func (msg *DescriptorProto) GetFieldDescriptor(fieldName string) *FieldDescriptorProto {
+	for _, field := range msg.GetField() {
+		if field.GetName() == fieldName {
+			return field
+		}
+	}
+	return nil
+}
+
+func (desc *FileDescriptorSet) GetEnum(packageName string, typeName string) *EnumDescriptorProto {
+	for _, file := range desc.GetFile() {
+		if strings.Map(dotToUnderscore, file.GetPackage()) != strings.Map(dotToUnderscore, packageName) {
+			continue
+		}
+		for _, enum := range file.GetEnumType() {
+			if enum.GetName() == typeName {
+				return enum
+			}
+		}
+	}
+	return nil
+}
+
+func (f *FieldDescriptorProto) IsEnum() bool {
+	return *f.Type == FieldDescriptorProto_TYPE_ENUM
+}
+
+func (f *FieldDescriptorProto) IsMessage() bool {
+	return *f.Type == FieldDescriptorProto_TYPE_MESSAGE
+}
+
+func (f *FieldDescriptorProto) IsBytes() bool {
+	return *f.Type == FieldDescriptorProto_TYPE_BYTES
+}
+
+func (f *FieldDescriptorProto) IsRepeated() bool {
+	return f.Label != nil && *f.Label == FieldDescriptorProto_LABEL_REPEATED
+}
+
+func (f *FieldDescriptorProto) IsString() bool {
+	return *f.Type == FieldDescriptorProto_TYPE_STRING
+}
+
+func (f *FieldDescriptorProto) IsBool() bool {
+	return *f.Type == FieldDescriptorProto_TYPE_BOOL
+}
+
+func (f *FieldDescriptorProto) IsRequired() bool {
+	return f.Label != nil && *f.Label == FieldDescriptorProto_LABEL_REQUIRED
+}
+
+func (f *FieldDescriptorProto) IsPacked() bool {
+	return f.Options != nil && f.GetOptions().GetPacked()
+}
+
+func (f *FieldDescriptorProto) IsPacked3() bool {
+	if f.IsRepeated() && f.IsScalar() {
+		if f.Options == nil || f.GetOptions().Packed == nil {
+			return true
+		}
+		return f.Options != nil && f.GetOptions().GetPacked()
+	}
+	return false
+}
+
+func (m *DescriptorProto) HasExtension() bool {
+	return len(m.ExtensionRange) > 0
+}