Convert TestEvent AMI events over to Stasis Core

This patch migrates the TestEvent AMI events to first be dispatched over the
Stasis-Core message bus. This helps to preserve the ordering of the events
with other events in the AMI system, such as the various channel related
events.



git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@384389 f38db490-d61c-443f-a65b-d21fe96a405b