Move o.o user creation to it's own manifest.

This patch creates a manifest for user creation that doesn't live in
base.  This is the first of several patches to abstract the
openstack_project module.  Moving user creation out to it's own
manifest will allow consumers of this module to optionally select
the user creation step.

This does not affect existing functionality.  It is a patch to
to add additional functionality later.

Change-Id: Ie96a28f1b05e4222dcc96b92357958a6b3276f96
Merge "Move o.o user creation to it's own manifest."