Updated openstack/openstack
Project: openstack/stevedore  d39ef75e58899db444a557494aefce065fe047fb

Fix requirement handling in tox

Move all test dependencies to test-requirements.txt and update
tox.ini to use that and the main requirements file to build the
virtualenv for testing. Remove redundant references to the different
requirements lists in other tox environment stanzas.

Change-Id: I1ff094778369ebfed567ebbb433ef487066f042a