ISPN-3530 ISPN-1855 Keep per-cache CH to route requests correctly

* fixed HotRodManagerIT tests: cannot pass null as cache name
ISPN-4472 Upgrade TestNG from 6.8 to 6.8.8
Use the proper configuration for the remote executor
Move the up handler deregistration to CommandAwareRpcDispatcher.stop
Logging improvements
TODO
Fix TestingUtil.clearContent for secure cache managers