[Fluxus] Turtle builder

[gabor papp]

hi Kassen,

> then it might make more sense to have this;
> 
> (with-turtle (get-transform))
> 
i think you are right, but since turtle is not a primitive, but a 
primitive builder, it would require much more changes than a couple of 
lines of code like the (get-turtle-transform) was. it would also infer 
other stuff like (build-turtle-builder), maybe using (rotate) and 
(translate) instead of (turtle-turn) and (turtle-move) like we discussed 
about the lights.

(define t (build-turtle-builder 'triangle-strip))

(with-turtle t
	(rotate #(30 0 0))
	(translate #(1 0 0))
	(turtle-vert)
	...
	(turtle-build-primitive))

additionaly, i think there are a couple of choices in fluxus that could 
be a bit more logical, like
- (turtle-prim) requires numbers to specify polygon face type instead of 
symbols as opposed to (build-polygons)
- you can either switch on or off a (hint-...), but not both.
- naming inconsistencies like (hint-wire), (wire-color), but 
(line-width), (line-pattern)

so it would need a lot of effort and discussion to find out how we could 
make fluxus more logical. on the other hand, we all got used to these 
things and probably prefer quickly adding new features than perfecting 
old ones. although it would be nice to collect and sort out these 
issues, and make fluxus more logical and easier to use.

best,
gabor