Let lame_client accept error status

Updated interop tests with support for compression.

A test suite for the RPC Framework base interface

I wasn't able to flesh this out nearly as much as I had wanted to but I
can come back to it after Beta (issue #2959).

php: fixed constant typo

docstrings for gprc_subchannel_{add,del}_interested_party

return StatusCode::INTERNAL for proto parsing error

The (new) base interface of RPC Framework

Remove the runtime dependency on the logging gem.

This is the public API of the old base package of RPC Framework
extracted into a first-class interface and adapted to metadata, status,
and flow control.

- provides a noop logger unless the user explicit adds a logging method
  to the GRPC namespace

Grpc ruby mv interop test to pb

Add parent call propagation API to Node library

- replaces it with a simple assertion function

- moves the client/server behaviour to pb/test
  - deprecate current bin/interop/interop_{client,server}.rb
- adds executable endpoints to bin
  - grpc_ruby_interop_{client, server}
  - these will be added to the ruby bin path when the grpc gem
    gem is installed, making them easier to execute

Use emplace_back properly, considering limitations of gcc 4.4

- Updates the code generated for the interop service
- Moves the generated interop service/client from bin to pb

Also
- removes an empty file from the health pb directories

Fix version of Google.Apis.Auth required by Grpc.Auth nuget.

Add a health checker service implementation.

Replaced remaining references to 'listen' with 'start'

Adds the remaining ruby interop tests

Grpc ruby add timeout interop test

Fixing zookeeper's installation.

- adds the code-generated health service classes to the pb along with
  a README explaining how to regenerate the generated code

- adds an implementation of the Health Checker Service along with unit
  tests and an integration test

Also:
- adds a pb folder
  : in a follow-up PR, all ruby pbs + generated code will be moved to it