Fixed: Radar did recognize Vehicles only as DetectableObjects

The "d as Vehicle" only works, if the Vehicle component is above the DetectableObject in the inspector.
Cleanup: removed duplicate ;
Comments: added more documentation for the parameters of Vehicle.IsInNeighborhood
Normalizing the calculated force of SteerForWander

Aparently it's convention to return normalized forces from CalculateForce() - wasn't aware when I re-implemented it (d618fa6)
Fixed: Limited Vehicle velocity

Calculating the newVelocity and instantly setting it another value discards the previous calculation. From the "Enforce speed limit" I guessed, the newVelecity should be clamped to MaxSpeed, not the acceleration