add appropriate copyright/license comments to generated svgs

[xenoterracide]

I use the python based tool reuse to ensure all of my files have an appropriate copyright and license. This is tricky when those files are generated by 3rd parties. The pretty images generated by the tool are not considered commented and so will cause the tool to error. While I can manually specify the copyright/license myself in the REUSE.toml I'm not actually certain what it is. For now I'm going to guess that it's the same as this repo. It would be good to have code generators generate an appropriate license in the svg's.