Merge pull request #146 from asadoughi/alembic_updates_6804

Added alembic revisions for missing indices, unique constraints
Removing pep8/flake reqs in test-reqs

Currently getting version mismatch on Travis tests.
MANY flake8 error fixes, all cosmetic
Many additional flake8 syntax fixes

More were found in the py26 env
And yet more flake8 fixes

Mostly import alphabetical order errors and space after multiline doc
Adding back # noqa to quota_driver import
And yet moar flake8 fixes
Last few flake8 changes, only H202s remain
Adding temporary # noqa to assertRaises

We need to go back and address this, by adding more specific exceptions to
the base code (i.e. the tests are not the problem). However, this is a hard
blocker currently, so putting it on the backburner for now.
Merge pull request #149 from insequent/pep8andflakefixes

Removing pep8/flake reqs in test-reqs