Write package names out to flat files

Write package names out to flat files

This patch updates all of the overcloud manifests so that
we write out flat files containing lists of the Puppet
packages which were managed by each manifest.

The flat files all get written to
/var/lib/puppet-tripleo/installed-packages/ where they can
be easily parsed by external tools. Example format from
the flat files looks like (for the controller step 1):

cat /var/lib/puppet-tripleo/installed-packages/overcloud_controller1
keepalived
haproxy

Depends-On: If3e03b1983fed47082fac8ce63f975557dbc503c

Change-Id: Ia324a08711796aa664f9c0273a051f4f2e3e92c9