Merge pull request #1466 from jbertram/master

XML exporter bug fixes
JBPAPP-10945: Logging a warning message when an inexisting role is defined in permissions.
Merge pull request #1469 from ehsavoie/JBPAPP-10945

JBPAPP-10945: Logging a warning message when an inexisting role is defined in permissions.
HORNETQ-1294 - Simplify the execution of the XML importer/exporter