Mullein

Copperbox revision 557.

I've changed the parameter in the score data types to make Pitch the hole rather than Element - Pitch is an attribute of Element, Element constructors include Note, Rest etc.

This simplifies things if I want to do LilyPond percussion notation for example. Percussion has the same elements (notes, rest, and chords - where chords are just different drums played simultaneously), but percussion pitches have the names of drums rather than regular pitch names like c4 (c in octave 4).