Generic Byte-Deep Raster Device

This Vplot filter outputs a byte-deep binary raster image, with whatever
dimensions you request. There is one 2-D image produced for each frame
in the Vplot input. (Break commands will also cause the image to be written.)
The "colfile" gives the (red,green,blue) color value associated with each
byte value in the raster image. Only byte values that are multiples of
"colormult" will be used (the Movie program here at Stanford only wants
even-valued bytes, since it uses odd-valued ones for its own purposes).

Raspen will create a file to put the raster image in FOR YOU if you
don't redirect it yourself, since you probably don't want to experience
what happens when you dump a huge binary raster file to your terminal.

Author - Joe Dellinger and Jeff Thorson
