Proto commits in public/sonora

These 9 commits are when the Protocol Buffers files have changed:

Commit:0d662ec
Author:Alex Stapleton
Committer:Alex Stapleton

Official interop test servers

The documentation is generated from this commit.

Commit:2dd1767
Author:Alex Stapleton

Remove the echo server It will be replaced by the official interop tests

Commit:4237eb9
Author:Alex Stapleton
Committer:Alex Stapleton

test streaming responses with metadata

Commit:54da4c8
Author:Alex Stapleton

Send and receive metadata

Commit:42bbdbd
Author:Alex Stapleton
Committer:Alex Stapleton

Refactor tests to take channels directly and add explicit timeout RPC test

Commit:644a862
Author:Alex Stapleton
Committer:Alex Stapleton

Benchmark protos

Commit:fd76ab4
Author:Alex Stapleton

Compile echo bindings

Commit:44d19b4
Author:Alex Stapleton

Raise grpc.RpcError in client when errors happen

Commit:82b8100
Author:Alex Stapleton

First version that passes some useful tests.