diff --git a/vendor/github.com/golang/protobuf/ptypes/empty/empty.pb.go b/vendor/github.com/golang/protobuf/ptypes/empty/empty.pb.go
new file mode 100644
index 0000000..b4eb03e
--- /dev/null
+++ b/vendor/github.com/golang/protobuf/ptypes/empty/empty.pb.go
@@ -0,0 +1,83 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// source: google/protobuf/empty.proto
+
+package empty
+
+import (
+	fmt "fmt"
+	proto "github.com/golang/protobuf/proto"
+	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
+
+// A generic empty message that you can re-use to avoid defining duplicated
+// empty messages in your APIs. A typical example is to use it as the request
+// or the response type of an API method. For instance:
+//
+//     service Foo {
+//       rpc Bar(google.protobuf.Empty) returns (google.protobuf.Empty);
+//     }
+//
+// The JSON representation for `Empty` is empty JSON object `{}`.
+type Empty struct {
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Empty) Reset()         { *m = Empty{} }
+func (m *Empty) String() string { return proto.CompactTextString(m) }
+func (*Empty) ProtoMessage()    {}
+func (*Empty) Descriptor() ([]byte, []int) {
+	return fileDescriptor_900544acb223d5b8, []int{0}
+}
+
+func (*Empty) XXX_WellKnownType() string { return "Empty" }
+
+func (m *Empty) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Empty.Unmarshal(m, b)
+}
+func (m *Empty) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Empty.Marshal(b, m, deterministic)
+}
+func (m *Empty) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Empty.Merge(m, src)
+}
+func (m *Empty) XXX_Size() int {
+	return xxx_messageInfo_Empty.Size(m)
+}
+func (m *Empty) XXX_DiscardUnknown() {
+	xxx_messageInfo_Empty.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Empty proto.InternalMessageInfo
+
+func init() {
+	proto.RegisterType((*Empty)(nil), "google.protobuf.Empty")
+}
+
+func init() { proto.RegisterFile("google/protobuf/empty.proto", fileDescriptor_900544acb223d5b8) }
+
+var fileDescriptor_900544acb223d5b8 = []byte{
+	// 148 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0x92, 0x4e, 0xcf, 0xcf, 0x4f,
+	0xcf, 0x49, 0xd5, 0x2f, 0x28, 0xca, 0x2f, 0xc9, 0x4f, 0x2a, 0x4d, 0xd3, 0x4f, 0xcd, 0x2d, 0x28,
+	0xa9, 0xd4, 0x03, 0x73, 0x85, 0xf8, 0x21, 0x92, 0x7a, 0x30, 0x49, 0x25, 0x76, 0x2e, 0x56, 0x57,
+	0x90, 0xbc, 0x53, 0x19, 0x97, 0x70, 0x72, 0x7e, 0xae, 0x1e, 0x9a, 0xbc, 0x13, 0x17, 0x58, 0x36,
+	0x00, 0xc4, 0x0d, 0x60, 0x8c, 0x52, 0x4f, 0xcf, 0x2c, 0xc9, 0x28, 0x4d, 0xd2, 0x4b, 0xce, 0xcf,
+	0xd5, 0x4f, 0xcf, 0xcf, 0x49, 0xcc, 0x4b, 0x47, 0x58, 0x53, 0x50, 0x52, 0x59, 0x90, 0x5a, 0x0c,
+	0xb1, 0xed, 0x07, 0x23, 0xe3, 0x22, 0x26, 0x66, 0xf7, 0x00, 0xa7, 0x55, 0x4c, 0x72, 0xee, 0x10,
+	0x13, 0x03, 0xa0, 0xea, 0xf4, 0xc2, 0x53, 0x73, 0x72, 0xbc, 0xf3, 0xf2, 0xcb, 0xf3, 0x42, 0x40,
+	0xea, 0x93, 0xd8, 0xc0, 0x06, 0x18, 0x03, 0x02, 0x00, 0x00, 0xff, 0xff, 0x64, 0xd4, 0xb3, 0xa6,
+	0xb7, 0x00, 0x00, 0x00,
+}
diff --git a/vendor/github.com/golang/protobuf/ptypes/empty/empty.proto b/vendor/github.com/golang/protobuf/ptypes/empty/empty.proto
new file mode 100644
index 0000000..03cacd2
--- /dev/null
+++ b/vendor/github.com/golang/protobuf/ptypes/empty/empty.proto
@@ -0,0 +1,52 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// 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.
+
+syntax = "proto3";
+
+package google.protobuf;
+
+option csharp_namespace = "Google.Protobuf.WellKnownTypes";
+option go_package = "github.com/golang/protobuf/ptypes/empty";
+option java_package = "com.google.protobuf";
+option java_outer_classname = "EmptyProto";
+option java_multiple_files = true;
+option objc_class_prefix = "GPB";
+option cc_enable_arenas = true;
+
+// A generic empty message that you can re-use to avoid defining duplicated
+// empty messages in your APIs. A typical example is to use it as the request
+// or the response type of an API method. For instance:
+//
+//     service Foo {
+//       rpc Bar(google.protobuf.Empty) returns (google.protobuf.Empty);
+//     }
+//
+// The JSON representation for `Empty` is empty JSON object `{}`.
+message Empty {}