What's New:
- Fixed crash when loading state, when the current program is an equation that is only referenced by SOLVE/INTEG internal variables.
- Changed Σ+/Σ- so that, in NSTK mode, they will accept a single real argument, assuming Y=0 in that case.
- Added STOP() function for equation debugging.
- In the equation editor, the named-equation catalog could select items from the wrong row.
- Fixed handling of LCLV of indexed matrix. It used to leave any pushed indexed matrix in limbo until RTN. With this change, the pushed indexed matrix is popped immediately.
- Tuned TONE frequencies to A440 scale.