BGI (Basic Graphical Instructions) to PostScript translator. Probably
not useful outside the Computer Centers. Added code to tie lines to
device space coordinates. Helps eliminate variations in line widths
noticeable when users selected a non-zero linewidth with the -w option.

Much that was omitted from early versions of the program has been
implemented. What's in place will handle most STARE (black and white)
and PRISM (color) BGI jobs. PRISM jobs often fill regions with color,
and need require device specific tuning to get things just right. An
easy solution is add "-P/prism true def" option to the postbgi command
line when you translate PRISM jobs.

A typical command line for STARE jobs would be,

	postbgi file >file.ps

while for PRISM jobs use,

	postbgi -P"/prism true def" file >file.ps