Add support for note head change on drum staves

It would be very useful for marching percussion notation where I want a different sound but the same note head. For example, when notating a snare flam, I've found that I get a better sound if I use a Visual note (upside down triangle notehead) as the grace note, because it's not two instances of the same exact sound cancelling or phasing each other out. Changing the grace note note gets the sound I want, but not the look I want, and it's a bit of a hassle fiddling with the master palette and visibility settings.