Add default auth_uri setting for auth token.

The latest keystoneclient code now gives a Warning if auth_uri
isn't explicitly specified.

Change-Id: I0feb52f7a9140ea750254f80b6a3e6855b25f1d3
Add missing puppet doc

Change-Id: Ic1620ba4e011f71a36e1958af140f0e696754dc1
Fail puppet-lint on warnings

Puppet-lint will now fail if there is any warnings.

Change-Id: I5997851548d32e4d723e4e76375cb17282c0d67b