Feature request: Add 1541Ultimate cartridge features

Hi,

It could be good and awesome add the 1541Ultimate cartridge features. It's true that nowadays you could use the OSD menu that it has some of same features but not all. Load as an external peripheric outside the OSD menu (with his own menu and his own configuration an setting options). 

Source:
https://github.com/GideonZ/1541ultimate/tree/master/target/fpga/u2plus_run


Regards,
Shark