Add ability to choose OS version in tests

This commit adds possibility to run kitchen
tests on different Openstack versions. By default
ocata release will be tested.

Also, run_tests.sh fixed to not to check pillars
which don't contain cinder dict.

Change-Id: Ie1d6b9a3f8e8e0d26852a5d010f88abdb1d75f71
Related-Prod: OSCORE-451
6 files changed