RPN83P: RPN calculator for TI-83+ TI-84+ inspired by HP-42S

[bxparks]

The next version (v0.11.0) of RPN83P is now available at https://github.com/bxparks/rpn83p/releases. Download the rpn83p.8xk file and transfer it to your 83+ or 84+ calculator. WARNING: The storage formats for the RPN stack and storage registers have changed again (this should be the last time... hahaha). They will be reset to 0 when you install and run this version.

I have refactored much of the RPN83P documentation. The User's Guide is now spread across 6 files, and comes to a total of 131 pages when converted to PDF:

• USER_GUIDE.md
• USER_GUIDE_BASE.md
• USER_GUIDE_COMPLEX.md
• USER_GUIDE_DATE.md
• USER_GUIDE_STAT.md
• USER_GUIDE_TVM.md
  

All screenshots that needed to be updated were retaken.

The changes I described previously for v0.11.0-dev remain valid. To summarize, the big changes for v0.11.0 are:

• new menu folder icon
• resizable RPN stack, 4 to 8
• resizable storage registers, 25 to 100
• scrollable input cursor, using LEFT and RIGHT arrow keys
• extract the 13 STAT registers into their own namespace, no longer overlap with R11-R23
• new BASE formatting: HEX digits grouped in 2's, OCT digits grouped in 3's, and BIN digits grouped in 4's
  

I'm particularly fond of the code that handles the scrollable input cursor. Because there's a heck of a lot of logic and edge-case handling going on, but it stays mostly out of the way, letting the user move around the input buffer easily and intuitively. Ironically, the code that handles this is basically incomprehensible to me, because it was too complex for me to write it in assembly from scratch. I tried, but failed several times. I had to write most of it in C, then compile it to assembly by hand, producing a chunk of code which is unmaintainable. I would have to go back to the C code to modify it, then recompile it down to assembly.

As usual, bug reports are welcome.

Brian