Implementing Netty-based GRPC Client Transport.  Server-side will be implemented in a follow-up CL.

Overview:
- NettyClientTransport - this is the entry point into the client transport. This creates streams as well as the NettyClientHandler

- NettyClientStream - client stream implementation. This sends commands to the NettyClientHandler via commands.  Callbacks on the stream are made directly from the NettyClientHandler in the channel thread context.

- NettyClientHandler - A Netty HTTP/2 handler that acts as a bridge between the NettyClientStreams and Netty's HTTP/2 processing.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=70970028
20 files changed
tree: 0011a05e4e2f2fa69bacb3fee57656be1a59d1e5
  1. core/
  2. stub/
  3. testing/
  4. LICENSE