Plus42 Equations, Preview Release

[Thomas Okken]

New update:

1. P/YR now restricted to integers in the range 1 to 999.
2. Displaying P/YR and BEGIN / END mode as a message when entering the TVM application menu, if the header isn't active (i.e. HEADER is off, or the display has fewer than 4 rows).

Not much going on until work starts on GRAPH...