Adds a new entity called "Radarsignal combinator"
When placed next to a radar it will output some signals for enemy units, worms and spawners (structures) which are in the visible area
It is unlocked with the "Advanced Radarsystems" technology

The idea was to have some sort of indication when enemy bases are near an outpost to then call the artillery train to show up

How it works
1. Place radar
2. Place new radar-signals combinator next to the radar
3. Set desired signals inside the combinator (Units, Worms, Spawners)
4. Connect to circuit network
5. Every 4th second it will output the amount of found entities based on given signals in the visible scanned area

Notes for mods
Works with all objects of type "radar" when they have set the parameter max_distance_of_sector_revealed > 0

Thanks
Thanks to folk for his Networked Radar mod which is the core of this one