Add compatibility with old themes

Hello!

I’ve been using BetterCampus for ages, and because of this, I have themes that I exported to my computer for safekeeping back when that was a function (specifically in version 5). Now there's no way for me to import those into the new BetterCampus, so I was wondering when you guys are going to add compatibility with that. I have so many themes I love and don’t want to lose. Whatever you can do to help is appreciated!