cluster should enable queue events in CATCHUP state

pavel moravec has discovered the mechanism for this problem already – current cluster code does not enable queue events until READY state – but new messages may be enqueued during CATCHUP state.
So if you have a replication-queue, which needs those queue-events to be generated, a newbie broker – if it is in CATCHUP state – will fail to replicate any messages that arrive on the replicated queue.
Two-line fix