Added verbose logs on failure

[MeirShpilraien]

The PR makes the following changes for better test reliability and error visibility:

1. Uses RLTest master branch so we will get full info on test failure (once we will have a new RLTest release, we should switch to it)
2. When running on cluster, wait for cluster to be initialized before starting the test.
3. Increase max idle time on specific tests to avoid flakiness on slow environment (like with Valgrind).