Mention licensing information in README

[ferki]

@krimdomu @ehuelsmann: this is the licensing information we discussed earlier briefly. IANAL, but I'd like to mention it in the README.

[ehuelsmann]

Yup. Fine by me.

[ehuelsmann]

@krimdomu ping

[krimdomu]

Fine for me

[ferki]

Fine for me

Thanks @krimdomu for stating your approval as a comment! Could you also approve it as a reviewer, please?

(Reasoning: it's possible to remove/edit the text of comments later, but approval seems to be logged as part of the issue history more permanently; I believe that's more formal/explicit, which feels like a better fit for the legal nature of question).

[ferki]

Based on my previous review of the repo, content by third party authors has been removed or rewritten. I believe that means if the three of us agrees on the new license, we can formally make the licensing change in order to make the contribution process smoother for future volunteers.

I'll do another review round later before merging.

[ehuelsmann]

@ferki time to close this PR?

[ferki]

@ehuelsmann: right, it wasn't merged yet, despite the initial agreement and approval, from the three of us.

My last notes about this topic say that all the previous contributors would also need to approve the license – or perhaps we can review all previous contributions, and see if we still ship them or not.

I have to admit I did not feel the motivation and capacity so far to do such a review in preparation to merge, while I still definitely would like to see a clearly applied license to this repo.