The method ApplySectorFilter() is used for pre-filtering an
osi3::SensorView.  It adds a margin of half a objects' diagonal to the
sensor range to also include objects which are just touching the cone,
but have their bounding box center outside the cone.

As it turns out, using the bounding box center as reference was wrong.
Instead, the osi3::MovingObject reference point has to be taken into
account (center of rear axle). Thus, the margin is increased to the full
diagnal of the object. This covers all cases where the rear axle center
is inside of the objects' bounding box.