Feature Models to 101wiki

[Lecram]

Basically, we agreed on modeling feature models at 101wiki

For now, we have two feature models that would need to be made explicit:

101companies
metalib

We might want to make the kind of description explicit that is presented here:
https://101wiki.softlang.org/Namespace:Feature

This still needs 1 or 2 discussion rounds. I just want to document this here.