This commit allows tempest to be configured to test the cinder backup
service.
Additionally, we:
- add a new function to openstack_tempest_gate.sh so we can include
some cinder-backup-related API tests in our test list
- update bootstrap-aio.sh to enable cinder backups and the ability to
test cinder backups
- update run-tempest.sh to include the cinder backup tests in the
default test list
Change-Id: I2b8b0255ef5fdf747bbc136c7b1152896161f8a0
Closes-Bug: #1449427
be0169ac5b