Allow deploying without Firebase, list alternate servers?

[customstickers]

So while #10 was being fixed I couldn't resist and made a clone using the sources here at https://customsticke.rs/ - it removes the Firebase dependency, to allow storing everything on a single server.

You don't seem to have a LICENSE file, so please let me know if you're fine with that. I can take it down quickly if you are not. :)

Anyway, since it's very ugly for now, I just did it to have it running ASAP, and I'm not even sure if I can keep it. Thus I could perhaps clean the changes up a bit and submit some patches later, if more people would be interested in running their own instances, for better redundancy. ;)

[manuel-di-iorio]

😂 😂