CLEAN note representation
CLEAN note representation

renamed and deleted following members:
- pitch has more sens than name, musicaly speeking
- duration is more time oriented than length
- start refers to the position of the note in the bar (or in the
stave) linking them together strongly. I think this information is
not likely to be contained in the note itself but should be bar/stave
oriented

ograndedjogo/tab-translator,ograndedjogo/tab-translator