Make the RabbitMQ settings more consistent

Modify the RabbitMQ password for all distributions using it, and provide
configuration informations for all the OpenStack services connected to
the message bus.

Change-Id: I6309c9080ab34885c68c11b5d37783e07bdd98bd
backport: havana
Closes-Bug: #1249230
Merge "Make the RabbitMQ settings more consistent"