Add ability to configure any catalog driver

Add a catalog_driver parameter which can be used to bypass
the catalog_type parameter and offer finer control over
the catalog driver configuration in Keystone.

Closes-bug: #1301592
Change-Id: If062c855c875cf06e192593181898ba0a185a91a
Merge "Add ability to configure any catalog driver"
Merge git://github.com/puppetlabs/puppetlabs-keystone