Use an IETF recommended domain name (example.org) in examples and
class parameter defaults instead of openstack.org. The only default
behavior change is for sender_email_address and the one site where
the default value would have been viable already has an override in
place to the same string anyway so this should result in no
effective behavior change.
Change-Id: I3e1bbb0bf4bfdd71f56cd429e890e90f2881bec5
ae299a57c0