Flatpack release

[titi]

This article made me think about making a flatpack release for linux too: https://www.gamingonlinux.com/articles/valve-are-looking-towards-flatpak-functionality-for-steam.8582

Maybe filux can comment on this  ;)

[filux]

I don't see a really good reason to use it yet :), ...but yeah it looks better than other competitors.
- not very popular yet,
- not enough easy to use for users (mostly because no gui),
- does not solve any problems for us which aren't already solved.