Merge branch 'master' into fix_3803

BUILD

Makefile

README.md

binding.gyp

build.yaml

config.m4

doc/connectivity-semantics-and-api.md

examples/cpp/helloworld/Makefile

examples/csharp/helloworld/.nuget/packages.config

examples/csharp/helloworld/Greeter/Greeter.csproj

examples/csharp/helloworld/Greeter/HelloworldGrpc.cs

examples/csharp/helloworld/Greeter/packages.config

...ples/csharp/helloworld/GreeterClient/GreeterClient.csproj

examples/csharp/helloworld/GreeterClient/packages.config

...ples/csharp/helloworld/GreeterServer/GreeterServer.csproj

examples/csharp/helloworld/GreeterServer/Program.cs

examples/csharp/helloworld/GreeterServer/packages.config

examples/csharp/helloworld/generate_protos.bat

examples/csharp/route_guide/.nuget/packages.config

examples/csharp/route_guide/RouteGuide/RouteGuide.csproj