Changes:
- workadventure is now pulled from stuebinm.eu/git via niv, and
should be updated automatically along with the other sources
- the same is true for the default map, which gets pulled directly from
its gitlab sources.
- this setup may potentially break things if I decide to rename an
option upstream, but I don't think that'll happen too often
- made the code a little nicer
- uses workadventure-xce now, since the tabascoeye version is now gone
Open for discussion:
- afaik know, the current version of workadventure-xce now contains
fediventure-specific patches. Do we want that, or should we switch
to the unfederated version?
