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/googleapi/internal/uritemplates/utils.go

@@ -0,0 +1,17 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package uritemplates
+
+// Expand parses then expands a URI template with a set of values to produce
+// the resultant URI. Two forms of the result are returned: one with all the
+// elements escaped, and one with the elements unescaped.
+func Expand(path string, values map[string]string) (escaped, unescaped string, err error) {
+	template, err := parse(path)
+	if err != nil {
+		return "", "", err
+	}
+	escaped, unescaped = template.Expand(values)
+	return escaped, unescaped, nil
+}