Add a bootstrap element:

Add a bootstrap element - a self-contained baremetal OpenStack,
which comes with default state such as keystone users and nova images.

- Add a nova-baremetal element
- Various fixes to glance element
- Combine glance-api and glance-reg elements, for now
- Add quantum configuration

Change-Id: Ib0c411627154a3d666f74513c6b8edfbfbf6c07e