Added policies and used policy enforcement engine
from monasca-common.
- Updated role_middleware to remove authorization into the routes.
- Updated unit tests and implemented some new tests.
- Added a new entry point for generating sample policy file by tox.
story: 2001233
task: 22086
Change-Id: I3d199fac244eca94fc434d19c78bc5a17e804c37
Signed-off-by: Amir Mofakhar <amofakhar@op5.com>