Remove NEST from community clients
[Docs] Add link to .NET client docs
Docs: Correct JSONP comment in config file

Due to the change of disabling JSONP by default in 1.3 we also need to
change the description in the configuration file.

Closes #7069
[TESTS] spin in a loop checking request breaker, because multiple clusters could be running
[TEST]: Enable sniff mode while testing

This adds randomization to enable sniff mode for the
transport client for each test run.
forced sniff mode when not disabled to make sure issues around sniff mode get revealed quickly
disabled sniff for a couple more tests that use dedicated masters