[Gemc_software] updates

[Maurizio Ungaro]

Happy Superbowl Friday ;-)

* a long standing issue has been fixed: users no longer need to order volume names alphabetically. 
* Geant4 9.5 and the latest gemc have been successfully installed on JLABL1 and JLABL2. It's not installed yet on ifarms but Computer Center is working on fixing some issues.
* Qt has not been upgraded to 4.8.0. CLHEP has been upgraded to 2.1.2.0.

The installation scripts have been updated accordingly.
Please let me know if you experience any problems.

regards,
mauri