- zint_symbol->fgcolour & bgcolour buffer lengths extended 10

-> 16 to allow for "C,M,Y,K" comma-separated decimal percentage
  strings
- API/CLI/GUI: allow foreground/background colours to be specified
  as comma-separated decimal "C,M,Y,K" strings where "C", "M" etc.
  are percentages (0-100) (ticket #281, 3rd point)
- output.c: new funcs `out_colour_get_rgb()` & `out_colour_get_cmyk()`
  and use in bmp/emf/gif etc.
- PCX: add alpha support
- GUI: fix fg/gbcolor icon background not being reset on zap
- GUI: Rearrange some Appearance tab inputs (Border Type <-> Width,
  Show Text <-> Font, Text/Font <-> Printing Scale/Size) to flow
  more naturally (hopefully)
- GUI: save button "Save As..." -> "Save..." and add icon
- CLI: add --bgcolor/colour & --fgcolor/colour synonyms

docs/zint.1.pmd

@@ -44,7 +44,8 @@ Paintbrush (`PCX`), Portable Network Format (`PNG`), Scalable Vector Graphic (`S
     "00002.png" etc., which can be changed by using the `-o` | `--output` option.
 
 `--bg=COLOUR`
-:   Specify a background (paper) colour where *COLOUR* is in hex `RRGGBB` or `RRGGBBAA` format.
+:   Specify a background (paper) colour where *COLOUR* is in hexadecimal `RRGGBB` or `RRGGBBAA` format or in decimal
+    `C,M,Y,K` percentages format.
 
 `--binary`
 :   Treat input data as raw 8-bit binary data instead of the default UTF-8. Automatic code page translation to an ECI
@@ -160,7 +161,8 @@ Paintbrush (`PCX`), Portable Network Format (`PNG`), Scalable Vector Graphic (`S
 
 `--fg=COLOUR`
 
-:   Specify a foreground (ink) colour where *COLOUR* is in hex `RRGGBB` or `RRGGBBAA` format.
+:   Specify a foreground (ink) colour where *COLOUR* is in hexadecimal `RRGGBB` or `RRGGBBAA` format or in decimal
+    `C,M,Y,K` percentages format.
 
 `--filetype=TYPE`