- Replaced use of bare '-1' values with StepParity::INVALID_COLUMN
- Removed StepParityGraph object, moved its responsibilities to StepParityGenerator
- Removed some unnecessary data from State object, added 'combinedColumns' and 'whatNoteTheFootIsHitting'
- Created stateCache to allow reuse of state objects
- Fixed a very small bug with TechCounts (missing 'previousPreviousHeel != INVALID_COLUMN')
Added convenience methods for determining if a given column is an up, down, or side arrow.
Added explicit tech counts for up footswitches and down footswitches