0.5.0

This is a very much unfinished development version of MonoSID. It's not really advisable to flash this unless you have a path back to the original MIDISID firmware, but I'm putting a .uf2 up so people who are interested in MonoSID can try things out easily.

While the basics work, flashing this firmware to your MIDISID's Pico is very much at your own risk.