HornetQUpgrade : A groovy script to upgrade the HornetQ version in JBoss AS 6.1.0

Add a script for upgrading HornetQ in JBoss AS 6.1.0 and the jarlibs of HornetQ version 2.2.24.
The jarlibs are located at SILVERPEAS_HOME/jar/hornetq and the script checks the actual version of HornetQ with the one with the installer before upgrading anything; the upgrade occurs only if the versions doesn't match.

Don't forget to merge also the commits into the master so that the changes will be also available in the future 5.12 release.