[fluxus] swings and roundabouts

[dave]

right then,

Executive summary: I've fixed the fluxus-in-drscheme problem, but broken
the fluxus app.

* fluxus and drscheme play nicely now, the fix is to get the latest svn
update of plt (it turned out to be an MrEd trying to delete random bits
of the fluxus internals)
* build updated to link against the 3m (new precice garbage collector)
version of mzscheme, which is now standard. I've updated the application
for this, but I'm getting some crashes on some of the scripts (which
hilariously now work fine in drscheme of course).
* lots of source documentation added - more to go
* added a GLSL=0 flag to the build to disable glew and hardware shading

So arg etc. But at least if it works in drscheme and breaks in the
fluxus editor I know it's my fault.

If you want to give the working bit a go, it's slightly convoluted using
fluxus in drscheme at present, you have to call everything in a
with-gl-context and between fluxus's low level begin-scene and end-scene
calls. There is no every-frame or any input, or camera - we'll set up a
nice environment for this, but I'll (try to) get 0.12 out first :)

cheers,

dave