Merge branch 'master' of github.com:grpc/grpc into server_auth_context

.gitmodules

.travis.yml

Makefile

build.json

composer.json

doc/interop-test-descriptions.md

include/grpc/grpc.h

include/grpc/support/cmdline.h

src/compiler/cpp_generator.cc

src/compiler/csharp_generator.cc

src/compiler/objective_c_generator.cc

src/compiler/ruby_generator.cc

src/core/channel/client_channel.c

src/core/iomgr/fd_posix.c

src/core/iomgr/fd_posix.h

src/core/iomgr/pollset_multipoller_with_poll_posix.c

src/core/iomgr/pollset_posix.c

src/core/support/cmdline.c

src/core/surface/call.h

src/core/surface/call_log_batch.c