update to allow test to receive multiple messages, plus some extra logging and renaming for clarity
add test that only receives some of the available messages in the transaction
only allow IOException's after socket closure to be suppressed, ensure other issues are actioned by the closer, e.g. unexpected data being read between the final handler and shutdown
fix up test to expect settlement of messages in the committed transaction
add brokerless integration test of rollback on a transacted session with a consumer