(was only set on BMP output to length of BMP pixel array)
EXCODE39: change to display check digit in HRT by default
CODE39/EXCODE39/LOGMARS: new hidden check digit option
(`option_2 = 2`)
qr.c: suppress bogus gcc-13 warning (only appears on optimize)
GUI: move some symbology-specific options into Data Tab so
separate tab unnecessary (those with few options and no
Composite/ECI), namely: all C25XXX, CODE39/EXCODE39/LOGMARS,
MSI_PLESSEY, CODABAR, DAFT, DPD, MAILMARK_2D, ITF-14, PZN,
UPNQR, CHANNEL, CODE93 and VIN, adjusting grp uis.
change Data dialog button (ellipsis) QToolButton -> QPushButton
& vice versa zap/clear/eye/swap/scale buttons QPushButton ->
QToolButton for better mac compat (also makes sense);
remove some mac hacks that no longer seem necessary;
use folder icon for Export dialog directory button
manual: document new Symbology-specific groupbox & CODE39/etc
hidden check digit option; add annexes on Qt and Tcl backends;
narrow some tables for better txt output;
remove echoed image tags in txt (pandoc 3.1.5 regression?);
add one-page HTML output to Makefile; also tex output (debug);
add class attributes to images to aid HTML styling;
various other fiddlings
