Merge branch 'master' into server_channel_affinity

BUILD

Makefile

binding.gyp

build.yaml

composer.json

config.m4

examples/cpp/helloworld/Makefile

examples/cpp/helloworld/greeter_async_client.cc

examples/cpp/helloworld/greeter_async_client2.cc

examples/objective-c/route_guide/ViewControllers.m

examples/python/helloworld/helloworld_pb2.py

examples/python/route_guide/route_guide_pb2.py

gRPC.podspec

grpc.gemspec

include/grpc++/impl/codegen/core_codegen_interface.h

include/grpc++/impl/codegen/proto_utils.h

include/grpc/byte_buffer_reader.h

include/grpc/impl/codegen/byte_buffer_reader.h

include/grpc/impl/codegen/grpc_types.h

include/grpc/impl/codegen/port_platform.h