[ODE] A fix for the bendy wheels (with code)

[Marco Grubert]

Hi Michael,

Good seeing you again :)

What is the trick to making this patch work ? If I call this function for
all my hinge2s, then it seems to make matters worse and given high enough a
rotation speed eventually the whole system explodes (the car does some
pretty cool loopings in the air, but it's not really what I am looking for).
Maybe it's a sign problem ?

- Marco Grubert

PS: Here's a funny little ODE demo created by one of our customers :
http://193.170.110.21/~toppl/physics_test.rar