Improve drum notation

Noteflight needs to add a rimshot option for drum set and marching percussion and a rim knock and/or rim click for drum set. Also add support for double stroke rolls and buzz rolls, flams, diddles, drags and cheeses for marching perussion. There should be an option to mix and match percussion staves to a single stave ex. add cowbell to basic percussion. In addition, all drum set parts should be separate voices or at least have that option. It would also be great to have a variety of cymbal and drum sounds and types and to be able to balance individual voices.