Add untested code for adding a collision shape to dynamics and proximity components based on the convex hulls of a model component.
Finish adding support for adding collision shapes to proximity and dynamics components of the convex hulls of the model component of the owner scene node.

This addresses issue #67 and does not yet include a visual wire-frame representation.
Add wireframe display for convex hull shapes on proximity and dynamics components.
Fix convex hull wireframes.
Have the scene editor update the model convex hulls of proximity and dynamics components when the model of the attached model component is reloaded.