Install Tempest in utility container

* Tempest playbook added to openstack dir
* glance_image module added for creating images and gathering image
  facts
* tempest_resources role added to create tempest prerequisites (cirros
  image, tenants)
* tempest role added for configuring tempest
* rpc_tempest_gate.sh added to /root in utility containers

(cherry picked from commit 7812cc49ea0094cb4a6f60c9faca0d79769933e5)
Create users within tempest tenants

(cherry picked from commit acda55d0a77fe361de6441d923c99aff777cdda3)
Merge pull request #299 from mancdaz/icehouse-tempest

Add tempest playbook to stable/icehouse