Merge pull request #1261 from ctiller/registered_calls

Makefile

include/grpc++/channel_interface.h

include/grpc++/impl/internal_stub.h

include/grpc++/impl/rpc_method.h

include/grpc++/impl/rpc_service_method.h

include/grpc/grpc.h

src/compiler/cpp_generator.cc

src/core/surface/channel.c

src/cpp/client/channel.cc

src/cpp/client/channel.h

src/cpp/client/generic_stub.cc

test/core/end2end/gen_build_json.py

test/core/end2end/tests/registered_call.c

tools/run_tests/tests.json