A "Reaper" input mode

[jukibom]

At least, I think that's what this issue was originally reported for...

An option to make left click place left hand notes and right click place right hand notes. Double click to delete.

May be worth using this ticket for any other shortcuts and stuff that might ease the transition for Reaper users?

[jukibom]

Middle click = grey note

[jukibom]

This would also need associated option / config file key and changes to the F1 panel

[Wolferacing]

I'm almost finished with the core code for this. Just have to fix a small bug involving melees.