[ODE] ODE changes

[Russ Smith]

i've checked in a number of changes:

* changed the way that the dInfinity constant is implemented: now it
  is #defined to be one of: FLT_MAX, DBL_MAX, HUGE_VAL, HUGE_VALF, or
  a large numeric constant. previously it was a variable that was
  exported from the library. this simplifies the configuration and
  build process quite a bit, especially in the case of DLLs.
	
* removed the old, deprecated collision system (geom.cpp,space.cpp,
  geom.h,space.h,odecpp_old_collision.h). the ODE_OLD_COLLISION
  configuration setting no longer has any meaning.
	
* removed support for dGeomGroups, which have been deprecated for
  a while and are equivalent to 'spaces' anyway.

NOTES
-----

i've updated the files in the VC6 directory, but haven't had the opportunity to test them.

i've updated the config.h in contrib/Mac_CFMCarbon, but i'm not sure if it works.

i have NOT fixed contrib/msvc7.


russ.

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