CaptureChangeMySQL does not stop if the queue is not empty

There is a logic bug in the handling of stopping the CaptureChangeMySQL processor. This causes it to not stop while there are events in the queue. If the processor isn't running fast enough to drain the queue, stopping the processor will have no effect.

The logic was being handled in OnStopped, but that won't get called until the onTrigger has finished. Instead the loop should be checking to see if the processor is still scheduled using isScheduled(), and if not should break out of the loop and finish the onTrigger processing, thereby allowing the OnStopped logic to be executed.