1. Correct PRD (03) to properly recognize control words on the tape
when B-modification of the input is also being done.
2. Temporarily add custom tracing of PRD, PRB, and PRI instructions.
3. Implement word counter on paper-tape panel to show current position
in the tape image.
1. Commit initial (incomplete) implementation of magnetic tape drives (TSU) and control: MLS, MRW, MDA, MIW, MIR, MPF, MPB, MPE, MIB, MIE.
2. Change B220SetCallback.js "setImmediate" mechanism to use DOM Promises instead of window.postMessage().
3. Minor styling and window positioning changes.
1. Implementation Paper Tape Reader devices and op codes.
2. Commit standard and inverse-format paper tape loaders for WINTER.PI program.
3. Fix positioning of Cardatron and TTY/Paper Tape Punch device windows.
