Merge pull request #43 from mirrorcoder/master

Refactoring cinder storage
Add cleanup_images action
Add flake8 into requirements.txt
Merge pull request #45 from Wasapl/master

Add flake8 into requirements.txt
Merge pull request #44 from miarmak/cleanup_images

Add cleanup_images action
Fix problem with multiple instances migration
Merge pull request #46 from miarmak/instances_fix

Fix problem with multiple instances migration
New scenario migration