Fix some memory leaks

Docker

Prevents a use-after-free

Prototype of gRPC C# library (Core and API examples)

Added a lot more information to Node README

Eliminate condvar in chttp2 transport

Fix contention in alarm lists

There's no need for this branch at all.

Theres no need for every thread to exit polling early if an alarm might finish, so there's no need to contend here.

Added missing pingpong tests to cloud prod test
Cleaned up test output and inserted them into a google.visualization.Datatable object

Fix up feature test macros

Add a tsan suppression file with OPENSSL_cleanse and use it in run_tests

Let the http2 transport issue a read request before pumping bytes into it.

Back-end for new core API

Fix a memory leak and a gpr_strdup/free mismatch in json_test

Fixing build.json by removing files that are no longer present.

Add a missing mdstr_unref

This fixes most of the asan reported leaks.

Make gpr_timespec no longer be a typedef for struct timespec in posix