Merge github.com:grpc/grpc into we-dont-need-no-backup

BUILD

build.json

gRPC.podspec

src/core/iomgr/tcp_windows.c

src/php/README.md

src/php/bin/run_tests.sh

src/php/ext/grpc/CREDITS

src/php/ext/grpc/LICENSE

src/php/ext/grpc/README.md

src/php/ext/grpc/package.xml

templates/gRPC.podspec.template

tools/doxygen/Doxyfile.core.internal

tools/jenkins/grpc_jenkins_slave/Dockerfile

vsprojects/grpc/grpc.vcxproj

vsprojects/grpc/grpc.vcxproj.filters

vsprojects/grpc_unsecure/grpc_unsecure.vcxproj

vsprojects/grpc_unsecure/grpc_unsecure.vcxproj.filters