[ODE] Breakable joints

[Roel van Dijk]

I thought it would be nice to have breakable joints in ode. You can do realy 
cool things with breakable joints. For instance a tank that looses it's 
turret when it is hit or (for the sadistic) bipeds that can loose limbs.
It is real easy to implement. 
I wrote a wrapper class for joints that handles things like when a joint 
should break, at what force or torque, and if it can break. After each 
physics step I call an update function that checks these conditions. If a 
break condition is met it detaches the joint. It works perfectly. I only have 
to think about what to do with the detached joints, but I think I can just 
throw them away.
What are your ideas on this? Could this be implemented in ode? It could 
certainly be more optimized then in my wrapper class and it could have more 
detailed break conditions. Maybe specialized for each joint type.

Roel van Dijk