Radar move from shop UI

[ZenBre4ker]

This moves the radar item to a SWEP and therefore eliminates the use of the equipment tab to manually trigger the radar.

Also I cleaned up the weird RADAR class and put it into a library. It now handles only the Target rendering of the Radar and of corpses, bombs and dna samples.

In this draft missing are sounds. Also the current weapon mesh is the radio, I thought to put it in another holding position to distinguish it a bit from the radio.