CODABLOCKF: prevent cols > 62; fix pTestList buffer overflow

RMQR: update to new draft ISO/IEC JTC1/SC31N000 (Draft 2019-6-24);
  allow for righthand vertical timing pattern in populate_grid()
ULTRA: update max size and min cols based on BWIPP 2021-07-14 update
backend_tcl/zint_tcl.dsp: use /MD instead of /MT for tcl lib compat;
  change include/lib path to more standard one
manual.txt: highlight that rMQR is still in development
GUI: use cross-platform smaller font func instead of explicit values for notes

backend/raster.c

@@ -299,8 +299,9 @@ static void draw_letter(unsigned char *pixelbuf, const unsigned char letter, int
         skip = 1;
     }
 
+    /* Following should never happen (ISBN check digit "X" not printed) */
     if ((textflags & UPCEAN_TEXT) && (letter < '0' || letter > '9')) {
-        skip = 1;
+        skip = 1; /* Not reached */
     }
 
     if (yposn < 0) { /* Allow xposn < 0, dealt with below */