[ODE] Sweep-and-Prune space for ODE

[Adam D. Moss]

Ah, so the SAP space doesn't care about the
size of the bounds of the volume within it?

That's a nice feature... it's the main reason
I switched back to using a HashSpace rather than
a QuadTreeSpace (because I couldn't reasonably guess
the size or origin of the encompassed volume at space
creation time).

I hope to try this out some time. :)

--Adam