Remove rhythmic-head-interface from AmbitusNoteHead and TrillPitchHead
This interface is for "rhythmic" heads, and these heads are not rhythmic. In practice, most engravers acknowledging this interface probably didn't expect these heads. The exception is Accidental_engraver
for TrillPitchHead
, which receives special consideration.
Fixes #1113 (closed)
Edited by Jean Abou Samra