Integration test refactoring

* Test for cluster configs was changed;
* Helper script for cluster config testing was changed;
* Test for Map Reduce was changed;
* Helper script for Map Reduce testing was changed;
* Test for Swift was changed;
* Added helper script for Swift testing;
* Test for scaling was changed;
* File base.py was changed;
* test-requirements.txt was changed;
* tox.ini was changed;
* Import of configs was changed: migration to Oslo config.

Implements blueprint itests-refactoring

Change-Id: I157e8aaf8a6542a79dd336650c978d096d40000b
Merge "Integration test refactoring"