http://www.grpc.io/docs/quickstart/go.html
http://www.grpc.io/docs/guides
http://www.grpc.io/docs/guides/concepts.html
http://www.grpc.io/docs/tutorials/basic/go.html
https://developers.google.com/protocol-buffers/docs/overview
https://github.com/google/protobuf/releases
https://segmentfault.com/a/1190000008672912 [http://www.tui8.com/articles/popular/90457.html ]
https://blog.1024coder.com/14766109567964.html
https://github.com/grpc/grpc/tree/master/doc
https://coreos.com/etcd/docs/latest/dev-guide/grpc_naming.html
localhost: OS X 10.10.3
$ git clone https://github.com/golang/text.git
$ go get google.golang.org/grpc
download protoc-3.3.0-osx-x86_64.zip from https://github.com/google/protobuf/releases
unzip it into /usr/local/protoc
$ echo "PATH=$PATH:/usr/local/protoc/bin" >> ~/.bash_profile
$ source ~/.bash_profile
$ go get -u github.com/golang/protobuf/{proto,protoc-gen-go}