Revision 1084175

https://issues.apache.org/jira/browse/AMQ-3236 - In the case of DLQ processing due to an exception from onMessage, provide the exception string as a message property. New property, org.apache.activemq.command.ActiveMQMessage#DLQ_DELIVERY_FAILURE_CAUSE_PROPERTY will hold the string form of the exception that causes a posion ack for a dlq message. It may be null if the cause was regular calls to rollback or message expiry. Wireformat change to have exception included with messageAck. new version 7