wumpus-basic

Copperbox revision 1948.

I've changed the representation of the Graphic type so it is function producing a pair. This makes it the same "shape" as the Image type, but as Graphic isn't "interesting" returns () in the left slot of the pair rather than a useful answer such as a bounding box. This unifies the graphic types in Wumpus-Basic so they are now largely the same "shape" - they vary only in the implicit arguments e.g. start-point, angle of rotation...

That said the code has got very messy again, I'll have to re-think the "combinator basis" in Kernel.Base.ContextFun as the current set don't seem to be helping me write uniform code.