[AI GENERIC] Law enforcement cars update

[Blackspots]

@natvander Some Texas counties use ghost markings and covert lighting. Hardeman and Wichita Counties are two examples.

[Laqueesha]

Here's a diagram showing all the uniforms used by the various state police forces in the U.S., if SCS decides to add unique policeman movers to states in ATS like they did with ETS2's countries.

[TitleMax]

Is there any way I can contribute textures to any SCS devs? I've made a few for some cities that don't currently have their own custom police cars.