For the most part this should be a pretty straight-forward
port of the run.yaml. The most complicated thing is executing
the post_test_hook.sh script. For that, a new post-run playbook
and role are added.
The relative path to devstack scripts in post_test_hook.sh itself
had to drop the 'new' directory since we are no longer executing
the script through devstack-gate anymore the 'new' path does not
exist.
Change-Id: Ie3dc90862c895a8bd9bff4511a16254945f45478