Add upload to Google Cloud Storage and Google Compute Image creation

- the image upload uses the cloud API
- currently auth and image creation need the `gcloud` CLI tool.

Signed-off-by: Justin Cormack <justin.cormack@docker.com>

vendor/google.golang.org/api/internal/settings.go

@@ -0,0 +1,37 @@
+// 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 internal supports the options and transport packages.
+package internal
+
+import (
+	"net/http"
+
+	"golang.org/x/oauth2"
+	"google.golang.org/grpc"
+)
+
+// DialSettings holds information needed to establish a connection with a
+// Google API service.
+type DialSettings struct {
+	Endpoint                   string
+	Scopes                     []string
+	ServiceAccountJSONFilename string // if set, TokenSource is ignored.
+	TokenSource                oauth2.TokenSource
+	UserAgent                  string
+	APIKey                     string
+	HTTPClient                 *http.Client
+	GRPCDialOpts               []grpc.DialOption
+	GRPCConn                   *grpc.ClientConn
+}