Collect CC0/CC-BY-SA assets usable for new modules

[falkTX]

Creating a discussion around assets that could potentially be reused by new modules.

Idea being that, if we want to add new stuff to Cardinal (either created from scratch or based on existing open-source code) we can have an easier time dealing with the panel creation and design.

A good-looking set of properly-licensed knobs, switches, etc in SVG format would be extremely useful.
We can have a look around the existing plugins, but the license situation with them is not always clear. And very rarely CC-BY-SA compatible.