CLOUDIFY-2340 clean manager rest project to comply with flake8 checks
Merge branch 'develop' into feature/CLOUDIFY-2340-flake8

Conflicts:
	manager-rest/manager_rest/resources.py
CLOUDIFY-2340 install flake8
CLOUDIFY-2340 fix bad merge
CLOUDIFY-2340 fix flake8 violations after merge
Merge branch 'develop' into feature/CLOUDIFY-2340-flake8
Merge pull request #122 from CloudifySource/feature/CLOUDIFY-2340-flake8

Apply flake8 rules to manager-rest project