XD-1824 Support RabbitMQ Cluster in source/sink

The rabbit connection factory supports cluster failover
by providing a list of `host:port` in the `addresses`
property.

Tested with:

`xd:>stream create foo --definition "time | rabbit --addresses=localhost:5672,10.0.0.3:5672" --deploy`
`xd:>stream create bar --definition "rabbit --queues=foo --addresses=localhost:5672,10.0.0.3:5672 | log" --deploy`

And shutting down local rabbitmq - failed over to remote.
Restart local, shutdown remote; failed back.
@ericbottard I am not sure what you're saying; both `host` and `port` have defaults; it worked for me with

"rabbit | log" (defaults) and

xd:>stream create bar --definition "rabbit --queues=hatest --addresses=10.0.0.3:5672,10.0.0.13:5672 | log" --deploy

What do I need to test to exhibit your suspected errant behavior?