t-rex 3.0.0

This is a terminal curses RPN calculator similar to the traditional calculators from Hewlett Packard. See https://www.hpmuseum.org/rpn.htm for info on RPN (Reverse Polish Notation). New in 3.0: Major XRPN integration with hybrid calculation modes, enhanced mathematical functions, program execution environment, program editor, base conversions, factorial safety, and comprehensive scrolling support.