+ 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.);

src/BulletCollision/CollisionShapes/btConvexHullShape.h

@@ -23,7 +23,7 @@ subject to the following restrictions:
 
 ///The btConvexHullShape implements an implicit convex hull of an array of vertices.
 ///Bullet provides a general and fast collision detector for convex shapes based on GJK and EPA using localGetSupportingVertex.
-ATTRIBUTE_ALIGNED16(class) btConvexHullShape : public btPolyhedralConvexShape
+ATTRIBUTE_ALIGNED16(class) btConvexHullShape : public btPolyhedralConvexAabbCachingShape
 {
 	btAlignedObjectArray<btVector3>	m_unscaledPoints;