Port Dead Letter Channel functionality of Carbon Business Messaging from MB 2.2 to MB 3.0.
Merge pull request #34 from sajinidesilva/slot_Imp

changed error logs
Merge pull request #35 from akalankapagoda/DLC

Port Dead Letter Channel functionality of Carbon Business Messaging from MB 2.2 to MB 3.0.
reverting to cql driver from cassandra driver
Merge pull request #36 from Asitha/reverting-to-cql

reverting to cql driver from cassandra driver
Improve exception handling and update copyright notice.
Update QpidServiceComponent.java
Merge pull request #38 from akalankapagoda/ExceptionHandling

Improve exception handling and update copyright notice.
added class level comment