C client library auth: produce adequate error codes and messages.

Remove C++11 dependencies in QPS test that break old compilers

Grpc ruby enable propagation between calls

Node fix auth interop

small fix for go docker private image building

Rename SingleValueHandler->SingleHandler, StreamHandler->EventHandler

Expose new core functionality to Python.

adding build.sh for go so that go can test with private changes and p…

fixing a go docker image build error.

Use common timeouts in Python face-layer test-cases.

Getting rid of unnecessary exception type

Disabled deprecation warnings in Node build

migrate to usable auth library

Fixing clock type for JWT verifier tool.

Expose per-call host override option in Node

C# code cleanup

Fix debug annotation typo in Python.

Removed "<:" bigram confusing gcc 4.4

Resulted in error:

```test/cpp/end2end/end2end_test.cc:120: error: ‘<::’ cannot begin a template-argument list
test/cpp/end2end/end2end_test.cc:120: note: ‘<:’ is an alternate spelling for ‘[’. Insert whitespace between ‘<’ and ‘::’
test/cpp/end2end/end2end_test.cc:120: note: (if you use ‘-fpermissive’ G++ will accept your code)
make: *** [objs/opt/test/cpp/end2end/end2end_test.o] Error 1```

Merge branch 'grpc-ruby-enable-propagation-between-calls' of github.com:tbetbetbe/grpc into grpc-ruby-enable-propagation-between-calls

Use null for default host