Merge github.com:google/grpc into batch-metadata

include/grpc/support/atm_win32.h

include/grpc/support/port_platform.h

src/core/iomgr/iocp_windows.c

src/core/iomgr/resolve_address_windows.c

src/core/iomgr/socket_windows.c

src/core/iomgr/tcp_client_windows.c

src/core/iomgr/tcp_server_windows.c

src/core/iomgr/tcp_windows.c

src/csharp/Grpc.Core/.gitignore

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

src/csharp/Grpc.Core/Grpc.Core.nuspec

src/csharp/Grpc.Core/packages.config

...rp/Grpc.IntegrationTesting/Grpc.IntegrationTesting.csproj

src/csharp/Grpc.IntegrationTesting/packages.config

src/objective-c/examples/Sample/Podfile

src/objective-c/examples/Sample/SampleTests/SampleTests.m

src/objective-c/examples/Sample/protos/Route_guide.pb.h

src/objective-c/examples/Sample/protos/Route_guide.pb.m

src/objective-c/examples/Sample/protos/Route_guide.podspec

src/objective-c/examples/Sample/protos/route_guide.proto