BZ #1173217 - Errors in /var/log/ceilometer/collector.log.

https://bugzilla.redhat.com/show_bug.cgi?id=1173217

The rabbit host/hosts values were being incorrectly set, causing ceilometer to
attempt to call rabbit on the incorrect IP.
Merge pull request #424 from jguiditta/BZ1173217-ceilo-rabbit-fix

BZ #1173217 - Errors in /var/log/ceilometer/collector.log.