Add os-config-applier to stackforge.

Change-Id: I6f7a9192b300ba8f2ad7dfc0302f1cf3c73716c5
Reviewed-on: https://review.openstack.org/25588
Approved: Jeremy Stanley <fungi@yuggoth.org>
Reviewed-by: Jeremy Stanley <fungi@yuggoth.org>
Tested-by: Jenkins