[ODE] new ODE collision

[Russ Smith]

if you're curious, the source files for the new collision infrastructure
have been checked into CVS (collision_*.h, collision_*.cpp). it has not
been hooked up to the rest of ODE yet, so the only reason i mention it
is for the curious. note that there's still a bunch of stuff to do, in
particular to hook up the ray, trimesh and cylinder classes, and to
convert the hash table space to use an incremental approach ... but you
can get an idea of the new layout.

the new collision infrastructure is 99% API compatible with the old, but
i'll provide an ODE 'legacy' collision option so that existing code is
guaranteed not to break - but all new collision development will go on
the new infrastructure.

russ.

-- 
Russell Smith
http://www.q12.org