Add threads list to debugger

This adds a list of threads to the debugger. It's read from the BIOS, and the position of the data can unfortunately vary. So I added a BIOS list which has that information. Currently only one BIOS is in the list, but it can easily be extended. It may even be in the same place for other BIOS versions.

All credit goes to @gregory38 for reverse engineering the internal structs.