JMS Source Does Not Expose `acknowledge`

Since the message-driven adapter uses a DMLC, the default behavior is to lose messages on exceptions (with the DMLC, the message is ack'd before the listener is invoked).

In order to provide recovery of such situations, the source needs to expose acknowledge so it can be set to transacted.

Or, perhaps, given that we don't expose complex configuration, the source should use a SimpleMessageListenerContainer instead (where the ack is sent after the listener is successfully invoked).