Multiversion authentication part2

Address last comments from part1:
- replace auth_data[0] with get_token()
- add token property to rest_client
- Remove comment about planned changes from config.py

Partially implements: bp multi-keystone-api-version-tests

Change-Id: Ia54cd3d824e44dd99d9226d4c0c6d6861d8c12ae
Use service catalog_type when getting the heat/glance clients

The 'orchestration' service_type is currently hard-coded when getting
the heat client but there is an orchestration.catalog_type config option
available, so use that rather than hard-code the value.

The same is true for the _get_image_client method and
CONF.image.catalog_type option, so fix that as well.

Change-Id: I6b4ba44619b9ddf99f063bc28c7c4bbae67408a8
Remove tox locale overrides

* tox.ini: The LANG, LANGUAGE and LC_ALL environment overrides were
introduced originally during the testr migration in an attempt to be
conservative about the possibility that locale settings in the
calling environment could cause consistency problems for test runs.
In actuality, this should be unnecessary and any place where it does
cause issues ought to be considered an actual bug. Also, having
these in the configuration actively causes older pip to have
problems with non-ASCII content in some package metadata files under
Python 3, so drop it now.

Change-Id: Iaf6006fd20031d423bc6ce47cfc604fe936ba5c2
Closes-Bug: #1277495
Merge "Use service catalog_type when getting the heat/glance clients"
Merge "Multiversion authentication part2"
Merge "Remove tox locale overrides"