[tripleo][openstack-ansible] Updates on collaboration on os_tempest role
During the starting of Denver 2018 PTG ., We started collaborating
towards using the
openstack-ansible-os_tempest role  as a unified tempest role in TripleO and
openstack-ansible project within OpenStack community.
It will help us to improve the testing strategies between two projects
which can be
further expanded to other OpenStack deployment tools.