Badge request: custom version compare

[mschubert]

Thanks for creating/maintaining repology including the web app! It's a great tool for me to track the package versions I maintain for the Archlinux AUR to see when I should update the PKGBUILDS (repository here).

For this, I've added badges that query the AUR version, which works great to get this overview (according to the usage docs):

[![toolname](https://repology.org/badge/version-for-repo/aur/toolname.svg?header=toolname)]

I'd like to create badges for a gentoo overlay that I maintain as well, however, the overlay is not tracked by repology (which I think is fine, it's mostly personal use).

However, I'd need to check if my provided version (let's say, snakemake=7.30.2) is still up-to-date with other distributions.

Would it be possible to add a custom version compare badge, similar to this?

[![toolname](https://repology.org/badge/version-for-repo/custom/toolname.svg?header=toolname&version=7.30.2)]