Now edit view will create and remove cameras and light gizmos properly
when cameras and lights are added or deleted.
Change-Id: I858752c1410f3a40ea2adaf538c281aaee94ec58
Fixes: QDS-1267
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>
Reviewed-by: Mahmoud Badri <mahmoud.badri@qt.io>
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>