Refactor reconfiguration into a management event
Refactor reconfiguration into a management event

Create a new management event queue to handle external requests
for actions that are not related to triggers or results.

Use this for reconfiguration events.  Subsequent patches will use
it for other kinds of events.

Change-Id: Ia018d9a7acc35aaf615ca85f75c9f4c630a5287f

gooddata/zuul,gooddata/zuul,wikimedia/integration-zuul,wikimedia/integration-zuul,devdattakulkarni/zuul_messaging,wikimedia/integration-zuul,gooddata/zuul,devdattakulkarni/zuul_messaging,devdattakulkarni/zuul_messaging,gooddata/zuul,wikimedia/integration-zuul,gooddata/zuul