Goal: 

• barbican-keystone-listener reads messages from RabbitMQ which are sent by Keystone.  Given that there will be no keystone in regionTwo, we need to figure out how barbican-keystone-listener in regionTwo (and other regionNs) will consume messages sent by Keystone in regionOne.
• Spike is needed to understand the queue type used by Keystone to send the messages.
• Both barbican-keystone-listeners in regionOne and regionTwo need to be able to consume the messages.
• We probably want to avoid making Barbican aware of the two different RabbitMQ instances
• Possibly we may be able to use a tool to mirror messages from regionOne into regionTwo by copying messages from one queue to the other.

Acceptance Criteria:

• Keystone in regionOne is publishing events on a queue that both barbican-keystone-listeners in regionOne and regionTwo are consuming.