Merge pull request #7161 from dgquintas/use_release

INSTALL.md

examples/cpp/README.md

examples/cpp/cpptutorial.md

examples/cpp/helloworld/README.md

examples/node/README.md

examples/objective-c/helloworld/README.md

examples/php/README.md

src/cpp/README.md

src/php/README.md

src/python/grpcio/README.rst

tools/distrib/python/grpcio_tools/README.rst