… happening during the transfer. Fix the problem partially: it can still occur if we dispatchLogs after the transfer message has been sent to the target, before it wins the election.

… changes: we weren't properly respecting stopCh.

…tionTimeout before resuming applies. Fix is in scare quotes because I'm not all sure this is acceptable.

…lel, and improve test log output.

…fail before responding to the transfer request.

…, which is racy in that in between calling pollState and setting up event monitoring, the cluster could've elected a leader. When that happens, Leader() errors returning 0 leaders.