Delete fixed_size_thread_pool

PHP: add unit test to increase PHP C extension code coverage

Revive and reform open-loop QPS testing

Add Census base log

PHP: add unit test to bring coverage back up above 95% (PHP portion)

Release 0.13 upmerge.

Adding the .yardopts file into the gems.

Adding a .yardopts file at the root so rubydocs isn't getting lost.

Update Node examples and example documentation

Copyright fix

since tsan slows things down a lot and may complicate issues such
as shutdown.

Upmerge from 0.13

Conflicts:
	Makefile
	build.yaml
	package.json
	setup.py
	src/core/surface/version.c
	src/csharp/Grpc.Core/VersionInfo.cs
	src/csharp/build_packages.bat
	src/python/grpcio/grpc_version.py
	src/ruby/lib/grpc/version.rb
	tools/doxygen/Doxyfile.c++
	tools/doxygen/Doxyfile.c++.internal
	tools/doxygen/Doxyfile.core
	tools/doxygen/Doxyfile.core.internal

Flagging 0.13.1-pre1.

Update Python doc

Flagging the release.

I also added some unrequested const's

Fix Python unit tests

Small tweak to make some customer code compile

Fixing the absence of 'tag' in the version.

Rename node qps worker to prevent confusion