cocrrected debug log
change type of arrival time to primitve Long to avoid NPEs
Merge pull request #147 from hastef88/queue_purge_feature_refactor

change type of arrival time to primitve Long to avoid NPEs
Merge pull request #148 from pamod/mqtt_dev

Fixing the issue encountered when un-subscribing from an MQTT topic
Merge pull request #146 from sajinidesilva/debug

corrected debug log
Adding licence headers, adding functionality to rollback during an exception occurs when adding the subscribers