diff --git a/vendor/github.com/googleapis/gnostic/extensions/README.md b/vendor/github.com/googleapis/gnostic/extensions/README.md
new file mode 100644
index 0000000..ff1c2eb
--- /dev/null
+++ b/vendor/github.com/googleapis/gnostic/extensions/README.md
@@ -0,0 +1,5 @@
+# Extensions
+
+This directory contains support code for building Gnostic extensions and associated examples.
+
+Extensions are used to compile vendor or specification extensions into protocol buffer structures.
diff --git a/vendor/github.com/googleapis/gnostic/extensions/extension.pb.go b/vendor/github.com/googleapis/gnostic/extensions/extension.pb.go
new file mode 100644
index 0000000..432dc06
--- /dev/null
+++ b/vendor/github.com/googleapis/gnostic/extensions/extension.pb.go
@@ -0,0 +1,300 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// source: extensions/extension.proto
+
+package openapiextension_v1
+
+import (
+	fmt "fmt"
+	proto "github.com/golang/protobuf/proto"
+	any "github.com/golang/protobuf/ptypes/any"
+	math "math"
+)
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion3 // please upgrade the proto package
+
+// The version number of OpenAPI compiler.
+type Version struct {
+	Major int32 `protobuf:"varint,1,opt,name=major,proto3" json:"major,omitempty"`
+	Minor int32 `protobuf:"varint,2,opt,name=minor,proto3" json:"minor,omitempty"`
+	Patch int32 `protobuf:"varint,3,opt,name=patch,proto3" json:"patch,omitempty"`
+	// A suffix for alpha, beta or rc release, e.g., "alpha-1", "rc2". It should
+	// be empty for mainline stable releases.
+	Suffix               string   `protobuf:"bytes,4,opt,name=suffix,proto3" json:"suffix,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Version) Reset()         { *m = Version{} }
+func (m *Version) String() string { return proto.CompactTextString(m) }
+func (*Version) ProtoMessage()    {}
+func (*Version) Descriptor() ([]byte, []int) {
+	return fileDescriptor_661e47e790f76671, []int{0}
+}
+
+func (m *Version) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Version.Unmarshal(m, b)
+}
+func (m *Version) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Version.Marshal(b, m, deterministic)
+}
+func (m *Version) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Version.Merge(m, src)
+}
+func (m *Version) XXX_Size() int {
+	return xxx_messageInfo_Version.Size(m)
+}
+func (m *Version) XXX_DiscardUnknown() {
+	xxx_messageInfo_Version.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Version proto.InternalMessageInfo
+
+func (m *Version) GetMajor() int32 {
+	if m != nil {
+		return m.Major
+	}
+	return 0
+}
+
+func (m *Version) GetMinor() int32 {
+	if m != nil {
+		return m.Minor
+	}
+	return 0
+}
+
+func (m *Version) GetPatch() int32 {
+	if m != nil {
+		return m.Patch
+	}
+	return 0
+}
+
+func (m *Version) GetSuffix() string {
+	if m != nil {
+		return m.Suffix
+	}
+	return ""
+}
+
+// An encoded Request is written to the ExtensionHandler's stdin.
+type ExtensionHandlerRequest struct {
+	// The OpenAPI descriptions that were explicitly listed on the command line.
+	// The specifications will appear in the order they are specified to gnostic.
+	Wrapper *Wrapper `protobuf:"bytes,1,opt,name=wrapper,proto3" json:"wrapper,omitempty"`
+	// The version number of openapi compiler.
+	CompilerVersion      *Version `protobuf:"bytes,3,opt,name=compiler_version,json=compilerVersion,proto3" json:"compiler_version,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *ExtensionHandlerRequest) Reset()         { *m = ExtensionHandlerRequest{} }
+func (m *ExtensionHandlerRequest) String() string { return proto.CompactTextString(m) }
+func (*ExtensionHandlerRequest) ProtoMessage()    {}
+func (*ExtensionHandlerRequest) Descriptor() ([]byte, []int) {
+	return fileDescriptor_661e47e790f76671, []int{1}
+}
+
+func (m *ExtensionHandlerRequest) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_ExtensionHandlerRequest.Unmarshal(m, b)
+}
+func (m *ExtensionHandlerRequest) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_ExtensionHandlerRequest.Marshal(b, m, deterministic)
+}
+func (m *ExtensionHandlerRequest) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_ExtensionHandlerRequest.Merge(m, src)
+}
+func (m *ExtensionHandlerRequest) XXX_Size() int {
+	return xxx_messageInfo_ExtensionHandlerRequest.Size(m)
+}
+func (m *ExtensionHandlerRequest) XXX_DiscardUnknown() {
+	xxx_messageInfo_ExtensionHandlerRequest.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_ExtensionHandlerRequest proto.InternalMessageInfo
+
+func (m *ExtensionHandlerRequest) GetWrapper() *Wrapper {
+	if m != nil {
+		return m.Wrapper
+	}
+	return nil
+}
+
+func (m *ExtensionHandlerRequest) GetCompilerVersion() *Version {
+	if m != nil {
+		return m.CompilerVersion
+	}
+	return nil
+}
+
+// The extensions writes an encoded ExtensionHandlerResponse to stdout.
+type ExtensionHandlerResponse struct {
+	// true if the extension is handled by the extension handler; false otherwise
+	Handled bool `protobuf:"varint,1,opt,name=handled,proto3" json:"handled,omitempty"`
+	// Error message.  If non-empty, the extension handling failed.
+	// The extension handler process should exit with status code zero
+	// even if it reports an error in this way.
+	//
+	// This should be used to indicate errors which prevent the extension from
+	// operating as intended.  Errors which indicate a problem in gnostic
+	// itself -- such as the input Document being unparseable -- should be
+	// reported by writing a message to stderr and exiting with a non-zero
+	// status code.
+	Error []string `protobuf:"bytes,2,rep,name=error,proto3" json:"error,omitempty"`
+	// text output
+	Value                *any.Any `protobuf:"bytes,3,opt,name=value,proto3" json:"value,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *ExtensionHandlerResponse) Reset()         { *m = ExtensionHandlerResponse{} }
+func (m *ExtensionHandlerResponse) String() string { return proto.CompactTextString(m) }
+func (*ExtensionHandlerResponse) ProtoMessage()    {}
+func (*ExtensionHandlerResponse) Descriptor() ([]byte, []int) {
+	return fileDescriptor_661e47e790f76671, []int{2}
+}
+
+func (m *ExtensionHandlerResponse) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_ExtensionHandlerResponse.Unmarshal(m, b)
+}
+func (m *ExtensionHandlerResponse) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_ExtensionHandlerResponse.Marshal(b, m, deterministic)
+}
+func (m *ExtensionHandlerResponse) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_ExtensionHandlerResponse.Merge(m, src)
+}
+func (m *ExtensionHandlerResponse) XXX_Size() int {
+	return xxx_messageInfo_ExtensionHandlerResponse.Size(m)
+}
+func (m *ExtensionHandlerResponse) XXX_DiscardUnknown() {
+	xxx_messageInfo_ExtensionHandlerResponse.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_ExtensionHandlerResponse proto.InternalMessageInfo
+
+func (m *ExtensionHandlerResponse) GetHandled() bool {
+	if m != nil {
+		return m.Handled
+	}
+	return false
+}
+
+func (m *ExtensionHandlerResponse) GetError() []string {
+	if m != nil {
+		return m.Error
+	}
+	return nil
+}
+
+func (m *ExtensionHandlerResponse) GetValue() *any.Any {
+	if m != nil {
+		return m.Value
+	}
+	return nil
+}
+
+type Wrapper struct {
+	// version of the OpenAPI specification in which this extension was written.
+	Version string `protobuf:"bytes,1,opt,name=version,proto3" json:"version,omitempty"`
+	// Name of the extension
+	ExtensionName string `protobuf:"bytes,2,opt,name=extension_name,json=extensionName,proto3" json:"extension_name,omitempty"`
+	// Must be a valid yaml for the proto
+	Yaml                 string   `protobuf:"bytes,3,opt,name=yaml,proto3" json:"yaml,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Wrapper) Reset()         { *m = Wrapper{} }
+func (m *Wrapper) String() string { return proto.CompactTextString(m) }
+func (*Wrapper) ProtoMessage()    {}
+func (*Wrapper) Descriptor() ([]byte, []int) {
+	return fileDescriptor_661e47e790f76671, []int{3}
+}
+
+func (m *Wrapper) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Wrapper.Unmarshal(m, b)
+}
+func (m *Wrapper) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Wrapper.Marshal(b, m, deterministic)
+}
+func (m *Wrapper) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Wrapper.Merge(m, src)
+}
+func (m *Wrapper) XXX_Size() int {
+	return xxx_messageInfo_Wrapper.Size(m)
+}
+func (m *Wrapper) XXX_DiscardUnknown() {
+	xxx_messageInfo_Wrapper.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Wrapper proto.InternalMessageInfo
+
+func (m *Wrapper) GetVersion() string {
+	if m != nil {
+		return m.Version
+	}
+	return ""
+}
+
+func (m *Wrapper) GetExtensionName() string {
+	if m != nil {
+		return m.ExtensionName
+	}
+	return ""
+}
+
+func (m *Wrapper) GetYaml() string {
+	if m != nil {
+		return m.Yaml
+	}
+	return ""
+}
+
+func init() {
+	proto.RegisterType((*Version)(nil), "openapiextension.v1.Version")
+	proto.RegisterType((*ExtensionHandlerRequest)(nil), "openapiextension.v1.ExtensionHandlerRequest")
+	proto.RegisterType((*ExtensionHandlerResponse)(nil), "openapiextension.v1.ExtensionHandlerResponse")
+	proto.RegisterType((*Wrapper)(nil), "openapiextension.v1.Wrapper")
+}
+
+func init() { proto.RegisterFile("extensions/extension.proto", fileDescriptor_661e47e790f76671) }
+
+var fileDescriptor_661e47e790f76671 = []byte{
+	// 362 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x74, 0x91, 0x4d, 0x4b, 0xeb, 0x40,
+	0x18, 0x85, 0x49, 0xbf, 0x72, 0x33, 0x97, 0xdb, 0x2b, 0x63, 0xd1, 0x58, 0x5c, 0x94, 0x80, 0x50,
+	0x44, 0xa6, 0x54, 0xc1, 0x7d, 0x0b, 0x45, 0xdd, 0xd8, 0x32, 0x8b, 0xba, 0xb3, 0x4c, 0xd3, 0xb7,
+	0x69, 0x24, 0x99, 0x19, 0x27, 0x1f, 0xb6, 0x7f, 0xc5, 0xa5, 0xbf, 0x54, 0x32, 0x93, 0xc4, 0x85,
+	0xba, 0x9b, 0xf3, 0x70, 0xda, 0xf7, 0x9c, 0x13, 0xd4, 0x87, 0x7d, 0x0a, 0x3c, 0x09, 0x05, 0x4f,
+	0x46, 0xf5, 0x93, 0x48, 0x25, 0x52, 0x81, 0x8f, 0x85, 0x04, 0xce, 0x64, 0xf8, 0xc5, 0xf3, 0x71,
+	0xff, 0x2c, 0x10, 0x22, 0x88, 0x60, 0xa4, 0x2d, 0xeb, 0x6c, 0x3b, 0x62, 0xfc, 0x60, 0xfc, 0x9e,
+	0x8f, 0xec, 0x25, 0xa8, 0xc2, 0x88, 0x7b, 0xa8, 0x1d, 0xb3, 0x17, 0xa1, 0x5c, 0x6b, 0x60, 0x0d,
+	0xdb, 0xd4, 0x08, 0x4d, 0x43, 0x2e, 0x94, 0xdb, 0x28, 0x69, 0x21, 0x0a, 0x2a, 0x59, 0xea, 0xef,
+	0xdc, 0xa6, 0xa1, 0x5a, 0xe0, 0x13, 0xd4, 0x49, 0xb2, 0xed, 0x36, 0xdc, 0xbb, 0xad, 0x81, 0x35,
+	0x74, 0x68, 0xa9, 0xbc, 0x77, 0x0b, 0x9d, 0xce, 0xaa, 0x40, 0xf7, 0x8c, 0x6f, 0x22, 0x50, 0x14,
+	0x5e, 0x33, 0x48, 0x52, 0x7c, 0x8b, 0xec, 0x37, 0xc5, 0xa4, 0x04, 0x73, 0xf7, 0xef, 0xf5, 0x39,
+	0xf9, 0xa1, 0x02, 0x79, 0x32, 0x1e, 0x5a, 0x99, 0xf1, 0x1d, 0x3a, 0xf2, 0x45, 0x2c, 0xc3, 0x08,
+	0xd4, 0x2a, 0x37, 0x0d, 0x74, 0x98, 0xdf, 0xfe, 0xa0, 0x6c, 0x49, 0xff, 0x57, 0xbf, 0x2a, 0x81,
+	0x97, 0x23, 0xf7, 0x7b, 0xb6, 0x44, 0x0a, 0x9e, 0x00, 0x76, 0x91, 0xbd, 0xd3, 0x68, 0xa3, 0xc3,
+	0xfd, 0xa1, 0x95, 0x2c, 0x06, 0x00, 0xa5, 0xf4, 0x2c, 0xcd, 0xa1, 0x43, 0x8d, 0xc0, 0x97, 0xa8,
+	0x9d, 0xb3, 0x28, 0x83, 0x32, 0x49, 0x8f, 0x98, 0xe1, 0x49, 0x35, 0x3c, 0x99, 0xf0, 0x03, 0x35,
+	0x16, 0xef, 0x19, 0xd9, 0x65, 0xa9, 0xe2, 0x4c, 0x55, 0xc1, 0xd2, 0xc3, 0x55, 0x12, 0x5f, 0xa0,
+	0x6e, 0xdd, 0x62, 0xc5, 0x59, 0x0c, 0xfa, 0x33, 0x38, 0xf4, 0x5f, 0x4d, 0x1f, 0x59, 0x0c, 0x18,
+	0xa3, 0xd6, 0x81, 0xc5, 0x91, 0x3e, 0xeb, 0x50, 0xfd, 0x9e, 0x5e, 0xa1, 0xae, 0x50, 0x01, 0x09,
+	0xb8, 0x48, 0xd2, 0xd0, 0x27, 0xf9, 0x78, 0x8a, 0xe7, 0x12, 0xf8, 0x64, 0xf1, 0x50, 0xd7, 0x5d,
+	0x8e, 0x17, 0xd6, 0x47, 0xa3, 0x39, 0x9f, 0xcc, 0xd6, 0x1d, 0x1d, 0xf1, 0xe6, 0x33, 0x00, 0x00,
+	0xff, 0xff, 0xeb, 0xf3, 0xfa, 0x65, 0x5c, 0x02, 0x00, 0x00,
+}
diff --git a/vendor/github.com/googleapis/gnostic/extensions/extension.proto b/vendor/github.com/googleapis/gnostic/extensions/extension.proto
new file mode 100644
index 0000000..04856f9
--- /dev/null
+++ b/vendor/github.com/googleapis/gnostic/extensions/extension.proto
@@ -0,0 +1,93 @@
+// Copyright 2017 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+syntax = "proto3";
+
+import "google/protobuf/any.proto";
+package openapiextension.v1;
+
+// This option lets the proto compiler generate Java code inside the package
+// name (see below) instead of inside an outer class. It creates a simpler
+// developer experience by reducing one-level of name nesting and be
+// consistent with most programming languages that don't support outer classes.
+option java_multiple_files = true;
+
+// The Java outer classname should be the filename in UpperCamelCase. This
+// class is only used to hold proto descriptor, so developers don't need to
+// work with it directly.
+option java_outer_classname = "OpenAPIExtensionV1";
+
+// The Java package name must be proto package name with proper prefix.
+option java_package = "org.gnostic.v1";
+
+// A reasonable prefix for the Objective-C symbols generated from the package.
+// It should at a minimum be 3 characters long, all uppercase, and convention
+// is to use an abbreviation of the package name. Something short, but
+// hopefully unique enough to not conflict with things that may come along in
+// the future. 'GPB' is reserved for the protocol buffer implementation itself.
+//
+option objc_class_prefix = "OAE"; // "OpenAPI Extension"
+
+// The version number of OpenAPI compiler.
+message Version {
+  int32 major = 1;
+  int32 minor = 2;
+  int32 patch = 3;
+  // A suffix for alpha, beta or rc release, e.g., "alpha-1", "rc2". It should
+  // be empty for mainline stable releases.
+  string suffix = 4;
+}
+
+// An encoded Request is written to the ExtensionHandler's stdin.
+message ExtensionHandlerRequest {
+
+  // The OpenAPI descriptions that were explicitly listed on the command line.
+  // The specifications will appear in the order they are specified to gnostic.
+  Wrapper wrapper = 1;
+
+  // The version number of openapi compiler.
+  Version compiler_version = 3;
+}
+
+// The extensions writes an encoded ExtensionHandlerResponse to stdout.
+message ExtensionHandlerResponse {
+
+  // true if the extension is handled by the extension handler; false otherwise
+  bool handled = 1;
+
+  // Error message.  If non-empty, the extension handling failed.
+  // The extension handler process should exit with status code zero
+  // even if it reports an error in this way.
+  //
+  // This should be used to indicate errors which prevent the extension from
+  // operating as intended.  Errors which indicate a problem in gnostic
+  // itself -- such as the input Document being unparseable -- should be
+  // reported by writing a message to stderr and exiting with a non-zero
+  // status code.
+  repeated string error = 2;
+
+  // text output
+  google.protobuf.Any value = 3;
+}
+
+message Wrapper {
+  // version of the OpenAPI specification in which this extension was written.
+  string version = 1;
+
+  // Name of the extension
+  string extension_name = 2;
+
+  // Must be a valid yaml for the proto
+  string yaml = 3;
+}
diff --git a/vendor/github.com/googleapis/gnostic/extensions/extensions.go b/vendor/github.com/googleapis/gnostic/extensions/extensions.go
new file mode 100644
index 0000000..94a8e62
--- /dev/null
+++ b/vendor/github.com/googleapis/gnostic/extensions/extensions.go
@@ -0,0 +1,82 @@
+// Copyright 2017 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package openapiextension_v1
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/golang/protobuf/ptypes"
+)
+
+type documentHandler func(version string, extensionName string, document string)
+type extensionHandler func(name string, yamlInput string) (bool, proto.Message, error)
+
+func forInputYamlFromOpenapic(handler documentHandler) {
+	data, err := ioutil.ReadAll(os.Stdin)
+	if err != nil {
+		fmt.Println("File error:", err.Error())
+		os.Exit(1)
+	}
+	if len(data) == 0 {
+		fmt.Println("No input data.")
+		os.Exit(1)
+	}
+	request := &ExtensionHandlerRequest{}
+	err = proto.Unmarshal(data, request)
+	if err != nil {
+		fmt.Println("Input error:", err.Error())
+		os.Exit(1)
+	}
+	handler(request.Wrapper.Version, request.Wrapper.ExtensionName, request.Wrapper.Yaml)
+}
+
+// ProcessExtension calles the handler for a specified extension.
+func ProcessExtension(handleExtension extensionHandler) {
+	response := &ExtensionHandlerResponse{}
+	forInputYamlFromOpenapic(
+		func(version string, extensionName string, yamlInput string) {
+			var newObject proto.Message
+			var err error
+
+			handled, newObject, err := handleExtension(extensionName, yamlInput)
+			if !handled {
+				responseBytes, _ := proto.Marshal(response)
+				os.Stdout.Write(responseBytes)
+				os.Exit(0)
+			}
+
+			// If we reach here, then the extension is handled
+			response.Handled = true
+			if err != nil {
+				response.Error = append(response.Error, err.Error())
+				responseBytes, _ := proto.Marshal(response)
+				os.Stdout.Write(responseBytes)
+				os.Exit(0)
+			}
+			response.Value, err = ptypes.MarshalAny(newObject)
+			if err != nil {
+				response.Error = append(response.Error, err.Error())
+				responseBytes, _ := proto.Marshal(response)
+				os.Stdout.Write(responseBytes)
+				os.Exit(0)
+			}
+		})
+
+	responseBytes, _ := proto.Marshal(response)
+	os.Stdout.Write(responseBytes)
+}