carto/protobuf @ php-ignore-enum

Jan Tattermusch 67fee07308 C#: set some dotnet options when testing		6 lat temu
..
build_nuget.bat	67fee07308 C#: set some dotnet options when testing	6 lat temu
continuous.cfg	847ee580f2 Add config files for testing csharp artifact (#5683)	6 lat temu
presubmit.cfg	847ee580f2 Add config files for testing csharp artifact (#5683)	6 lat temu
release.cfg	f3d3bfc01e add scripts for automated building of C# nuget on Kokoro	7 lat temu