Merge github.com:grpc/grpc into primary-goat-whisperer

Makefile

README.md

src/core/iomgr/sockaddr_utils.c

src/core/iomgr/tcp_server_windows.c

src/core/surface/channel.c

src/cpp/client/channel.cc

src/cpp/client/channel.h

src/cpp/client/create_channel.cc

src/cpp/client/insecure_credentials.cc

src/cpp/client/secure_credentials.cc

src/csharp/Grpc.Auth/OAuth2Interceptors.cs

src/csharp/Grpc.Core.Tests/ChannelTest.cs

src/csharp/Grpc.Core.Tests/ClientServerTest.cs

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

src/csharp/Grpc.Core.Tests/NUnitVersionTest.cs

src/csharp/Grpc.Core.Tests/TimeoutsTest.cs

src/csharp/Grpc.Core/Channel.cs

src/csharp/Grpc.Core/ChannelOptions.cs

src/csharp/Grpc.Core/ChannelState.cs

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