[GRASS5] Hex equivalents of grass colors?

[Hamish]

> >> This is information is on my wish list too. I found it in:
> >> http://freegis.org/cgi-bin/viewcvs.cgi/grass6/lib/gis/color_str.c
..
> > However, this doesn't exactly match the colours used by the display
> > drivers. Both the PNG and X drivers use:
..
> > The main differences are for magenta and grey. The driver's magenta
> > is definitely wrong, as magenta is supposed to be one of the corners
> > of the RGB cube; maybe those values should be used for violet?


also note ps.map has it's own version, which should probably be brought
into the fold.

https://intevation.de/rt/webrt?serial_num=3049


Hamish