Doc Fixit: src/cpp/README.md

Replace liquid templates with relative links.

Doc Fixit: examples/cpp/helloworld/README.md

Adding a python_wrapper.sh script to call in an appropriate python2 interpreter

More fixes for performance benchmarking code

Update documentation to refer to yaml, not json

Fix minor issues with Ruby route guide client

Don't use a pipe for output capturing in Python's test runner

DocFixit: Minor corrections to the instructions

Add debug support for checking tls_init is called

Clean up a core test

Use 'RegisterService' for registering async services.

DocFixit: Python README

Factor out backoff code into a separate library (to be re-used elsewhere)

Apparently Python can call arbitrarily deallocation code whenever its
allocator is invoked, which can cause output from gRPC core to stderr,
which can happen on the thread that is emptying the stderr pipe, thus
causing the stderr pipe to deadlock on itself.

Update check copyright script precommit hook

Add intial plaform support for Native Client (NaCl)

Added codegen_lib

Remove end2end_certs library.

Get callstacks for test failures on Windows

Don't hold the GIL when calling anything in core

Codegen massage