add licensing to the project

[cr1tbit]

Before merging to main, we want to make sure the licensing has no mistake in it.

Pasting the image of the licenses on the PCB for reference:

[cr1tbit]

The licensing text:

Licensing Information

The hardware design files, including schematics and PCB layout (excluding silkscreen artwork and outline design), are licensed under the CERN Open Hardware Licence v2 CERN-OHL-W.

Artwork and outline design © 2023 by Ewa Kielska are licensed under CC BY-NC-ND 4.0

All documentation is released under CC BY-SA 4.0

In summary, you are free to use schematic and general concept of this project according to CERN-OHL-W license. If you want to include the artwork, you must adhere to CC BY-NC-ND 4.0 too.

We are open to either adjust these licensing terms, or providing the design files with alternative licensing terms in special cases. Feel free to open issue then.