fixed: new GetIntersection(Sphere, Sphere, Circle) did not normalize the  normal of the intersection circle (os the old code did)
fixed: new GetIntersection(Sphere, Sphere, Circle) did not normalize the
 normal of the intersection circle (os the old code did)

tkemmer/ball,tkemmer/ball,tkemmer/ball,tkemmer/ball,tkemmer/ball,tkemmer/ball