Ignore H302 as other TripleO projects

Ignore H302 "Do not import objects, only modules" rule.

This is in accordance with other TripleO projects and will allow
e.g. importing the translation function `_`.

Change-Id: I5c27d77334a1e75318302d6330cf1a0c670a940a
WIP Keystone setup

Adds gettextutils (translations) to openstack-common.conf.

Adds mock dependency for testing.

Implements: blueprint tripleo-keystone-cloud-config

Change-Id: I8ad106c4dbf793bada4e4a1141256ac72bb653db