merge to take src/core componentization into account

BUILD

Makefile

binding.gyp

build.yaml

config.m4

doc/interop-test-descriptions.md

gRPC.podspec

grpc.gemspec

include/grpc++/generic/async_generic_service.h

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

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

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

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

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

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

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

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

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

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

include/grpc++/support/byte_buffer.h