Fix GCS

Signed-off-by: Olivier Gambier <olivier@docker.com>

vendor/google.golang.org/grpc/README.md

@@ -2,22 +2,31 @@
 
 [![Build Status](https://travis-ci.org/grpc/grpc-go.svg)](https://travis-ci.org/grpc/grpc-go) [![GoDoc](https://godoc.org/google.golang.org/grpc?status.svg)](https://godoc.org/google.golang.org/grpc)
 
-The Go implementation of [gRPC](https://github.com/grpc/grpc)
+The Go implementation of [gRPC](http://www.grpc.io/): A high performance, open source, general RPC framework that puts mobile and HTTP/2 first. For more information see the [gRPC Quick Start](http://www.grpc.io/docs/) guide.
 
 Installation
 ------------
 
-To install this package, you need to install Go 1.4 and setup your Go workspace on your computer. The simplest way to install the library is to run:
+To install this package, you need to install Go 1.4 or above and setup your Go workspace on your computer. The simplest way to install the library is to run:
 
 ```
 $ go get google.golang.org/grpc
 ```
 
+Prerequisites
+-------------
+
+This requires Go 1.4 or above.
+
+Constraints
+-----------
+The grpc package should only depend on standard Go packages and a small number of exceptions. If your contribution introduces new dependencies which are NOT in the [list](http://godoc.org/google.golang.org/grpc?imports), you need a discussion with gRPC-Go authors and consultants.
+
 Documentation
 -------------
-You can find more detailed documentation and examples in the [grpc-common repository](http://github.com/grpc/grpc-common).
+See [API documentation](https://godoc.org/google.golang.org/grpc) for package and API descriptions and find examples in the [examples directory](examples/).
 
 Status
 ------
-Alpha - ready for early adopters.
+Beta release