Add Legal stuff

[itrich]

We need the usual legal stuff, Impressum, etc.

[itrich]

@fkr is happy to be the guy on the legal page

[fkr]

as discussed, I withdrew this offer.

[itrich]

as discussed, I withdrew this offer.

Thank you nevertheless! I'll take care of this as discussed.

[itrich]

This issue is currently blocked by pending discussions. A solution can hopefully be aimed for March 2023.