Small cleanups:
* Use openstack-lower-constraints-jobs template, remove individual
jobs.
* Sort list of templates
* Remove install-guide-jobs template, this stayed in project-config
and is wrong on this branch.
* Remove branches condition, there's an implicit one, this is not
needed.
* Remove job tripleo-ci-centos-7-scenario002-multinode-oooq that
only runs in pike, it gets ignored in this file.
Import job legacy-rally-dsvm-zaqar-zaqar and rename according to
Zuul v3 naming conventions.
Change-Id: Ic18f76fef2b139a3edefecc6004846b11ee7653e
49d6cfaaf8