Use templates for cover and lower-constraints
Use templates for cover and lower-constraints

Use openstack-tox-cover template, this runs the cover job
in the check queue only.

Use openstack-lower-constraints-jobs template

Remove jobs that are part of the templates.

Sort list of templates.

Change-Id: Ie7971023eed04f6479c05c1d2a1dfd2a948b07e1

openstack/taskflow,jimbobhickville/taskflow,openstack/taskflow,jimbobhickville/taskflow