Download link to installer on website points to old version

The website (https://www.fz-juelich.de/ias/ias-7/EN/Expertise/Software/PeTrack/petrackDownload.html?nn=2317856) still points to an old version of the installer and not the new one uploaded to sciebo. Also we should decide on the naming of the installer, currently petrack-installer-MAJOR.MINOR.PATH, to get a permanent link.