[ODE] Flat cylinder geom come to life!

[Nguyen Binh]

Hi Adam,

ADM> I think the plan roughly agreed on the list was to promote this to
ADM> a full in-core geom when the collision cases are approaching
ADM> completeness.

     For planning, here is my TODO in Cylinder collider:
     
     There are two original Croteam's colliders left:
     + Cylinder vs Cylinder : Definitely important and I'll finish it
     very soon
     + Cylinder vs capsule  : hmm.. not so important but I'll work on
     it after fixing the bug in cylinder vs cylinder

     So there are no cylinder vs plane in Croteam's side. (Am I right
     Alen ???). And IMHO, cylinder vs plane is very important because
     plane is very good for ground representation, so I may try to
     write it myself follow the methods of current Croteam's
     colliders. I expect it won't take me too long.
     
     + Then we really need a good demonstration of cylinder collider :
     maybe a drivable buggy with cylinders as wheel?

     Nguyen Binh.