Improve system_tests
Update documnetation
One more refactoring of system_tests
Fix cluster creation in HA mode. Removed unused update cluster mode function
Fix typos
Merge pull request #1507 from dmitryilyin/system_tests

Rather big refactoring of system tests script
Merge pull request #1519 from Mirantis/fix-cluster-ha

Fix cluster creation in HA mode.
Merge branch 'master' into mirrorfix
ubuntu repo creation
ubuntu repo creation
ubuntu debs
another step to mirror creation