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

Makefile

build.json

src/compiler/csharp_generator.cc

src/compiler/generator_helpers.h

src/compiler/objective_c_generator.cc

src/compiler/objective_c_generator.h

src/compiler/objective_c_generator_helpers.h

src/compiler/objective_c_plugin.cc

src/core/iomgr/pollset_posix.c

src/core/surface/call.c

src/core/surface/completion_queue.c

src/core/surface/server.c

src/core/transport/chttp2/frame.h

src/core/transport/chttp2/frame_rst_stream.c

src/core/transport/chttp2/frame_rst_stream.h

src/core/transport/chttp2_transport.c

src/csharp/Grpc.Core.Tests/Grpc.Core.Tests.csproj

src/csharp/Grpc.Core.Tests/packages.config

src/csharp/Grpc.Core/AsyncClientStreamingCall.cs

src/csharp/Grpc.Core/AsyncDuplexStreamingCall.cs