Changeset 7006 for extensions/jiwigo

adds a script to generate the executables under a GNU/Linux environnement.
It generates .exe file and deb and copies the exe, deb, jar, src.tar.gz in a separate folder. The mvn jar command must be run before launching this script, and
the file ​http://www.le-guevel.com/jiwigo/downloads/travail.tar.gz must be downloaded and extracted.
Then two variables of the script should be changed :
travail_path and project_path
The script does not take parameters.