fixes #269: MamdaSubscription redundantly creates Exception instance in onMsg
fixes #269: MamdaSubscription redundantly creates Exception instance in onMsg

only creating an Exception if msgType is MamaMsgType.TYPE_DELETE

fquinner/OpenMAMA,fquinner/OpenMAMA,fquinner/OpenMAMA,fquinner/OpenMAMA,fquinner/OpenMAMA,fquinner/OpenMAMA,fquinner/OpenMAMA