Add Gaia 2.0 support

I optimized VersionControl.php so that we don't have to change it anymore + using locales in context (did a few tests, looks like it works)
Also, we'll need to run setup.sh then glossaire.sh once it's merged.
I think we should only display the warning, not exit. So: if missing -> display error, else do the job.
As it is, if a folder does not exist, we stop everything.