+ Internal improvements for collision shapes

1) add AabbCaching versions of btPolyhedralConvexShape and btMultiSphereShape (this speeds up btMultiSphereShape 'getAabb', and reduces size of btBoxShape)
2) btCylinderShape doesn't derive from btBoxShape anymore
+ Minor fixes in drawing for btMultiSphereShape, btBoxShape.
+ Don't re-generate btDebugFont every frame
+ Disabled velocity prediction for btDbvtBroadphase. Previous default can be restored using btDbvtBroadphase->setVelocityPrediction(1./2.);

Demos/Gpu2dDemo/BasicDemo.h

@@ -66,6 +66,9 @@ class BasicDemo : public GlutDemoApplication
 
 	void	exitPhysics();
 
+	///don't shoot a box in this demo ;-)
+	virtual void	shootBox(const btVector3& dest) {}
+
 	virtual void clientMoveAndDisplay();
 
 	virtual void displayCallback();