Add an option to disable radar event for detecting cloaked units

    When player has TechnoTypes with a really large SensorsSight, the radar event can be abused and annoying if there are many cloaked units arround. It also makes the "space" shortcut almost useless since the screen will always jumps to the detected units.
    Possible rulesmd.ini code:
[General]
RadarEvent.Disable=(list of integers, which refer to specific kinds of radar event. In this case, it should be 6)