Staff notation mode

[rwtnb]

Some drummers get used to reading the semi-standardized staff notation, so having a mode that shows the symbols like that (circles, crosses, etc) at the right lanes might help. Of course, staff notation also specifies the duration of each note, and that might not be available depending on the source format of the drum notes file, and probably would be way too hard to implement. But at least the cross vs. circle and the specific lanes would make it easier when your brain has already learned that.