Introduce run_full_performance.sh and support 32core scenarios

Simplify profiling in C# qps clients.

C# assorted cleanup

Fix code coverage.

Add very much needed documentation for tools/run_tests/ directory

Assert we get a valid creds.

Make qps workers connect before even warmup stage begins

Correct assertion for single FD being orphaned.

Manual merge of 0.14 branch into master.

PHP: update package.xml after fixes