wumpus

Copperbox revision 2383.

Minor updates.

I've added ASCII art to Wumpus-Basic to illustrate line caps and joins - this means I won't have to look at the PostScript language guide when I need to know which is which.

Wumpus-Drawing gets a new module for primitive graphics (lines, etc.) which will get fleshed out over time. This module has to be electively imported so it can be more direct about its it naming scheme than DrawingPrimitives in Wumpus-Basic. The latter is imported globally as part of Wumpus.Basic.Kernel so it uses the dc prefix to avoid name clashes.