updating  Rabbit MQ transport fixing compatibilities. Merging the fix https://wso2.org/jira/browse/CARBON-14850 to git.
Merge branch 'modify_rabbitMQ_transport' of https://github.com/abeykoon/wso2-axis2 into abeykoon-modify_rabbitMQ_transport
Merge branch 'abeykoon-modify_rabbitMQ_transport' into release-1.6.1-wso2v11