Add packages to devstack launch slave.

rackspace-auth-openstack and sqlite3.

Change-Id: Id8d0633c29399db5bbdd559a75ba2c6d6096b4ea
Reviewed-on: https://review.openstack.org/24490
Reviewed-by: Jeremy Stanley <fungi@yuggoth.org>
Approved: Monty Taylor <mordred@inaugust.com>
Reviewed-by: Monty Taylor <mordred@inaugust.com>
Tested-by: Jenkins