Add license

[darigovresearch]

Probably makes sense to keep it consistent with the same license as the Precious plastic download kits

[darigovresearch]

@davehakkens can you advise on what you expect the license for this download kit to be?

It would help for derivative works which may be later merged even if the kit is in the early stages - https://github.com/darigovresearch/Project-Kamp-Solar-Setup