Mount /usr/lib/heat on undercloud Heat
Mount /usr/lib/heat on undercloud Heat

We need the tripleo common on the undercloud heat, let's mount an
additional volume to share them.

Change-Id: If306862f5a9b7455165523ab7b8350d18395edb7
Closes-Bug: #1784569

openstack/tripleo-heat-templates,openstack/tripleo-heat-templates,dprince/tripleo-heat-templates,dprince/tripleo-heat-templates