Further integration of scaleDegree
Further integration of scaleDegree

Use procedures already in place for parsing string and
returning accidental markup.

This has the benefit of allowing any of the English accidentals
as a prefix, not that sharps, flats, and naturals aren't enough...

TODO: How do we deal sensibly with non-accidental modifiers?  Right
now if an accidental prefix is not found, it is grouped with the
number.  Thus, the caret is centered over both number and
unrecognized character(s).

noteflakes/lyp-roman-numerals