Roles RBAC test for Keystone API v2 roles

- migrate out common clients and internal methods to the base
- fixes to projects rbac test to use tempest base instead
- using the setups in tempest identity base instead of internals
- Migrating the identity roles rbac tempest test to Patrole

Partially-Implements bp: initial-tests-identity
Co-Authored-By: Cliff Parsons <cp769u@att.com>

Change-Id: I8f0d10fbfa047c53d2ea801eb531caa24a5b51a0
3 files changed