MAN TGS 18.500

The following has been realized so far:
- Motor configuration selectable (18,440 / 18,480 / 18,500)
- Standard engine is the 18,440
- Power: 400 hp / 480 hp / 500 hp
- 2 tire configurations added (Nokian Kommunal / Michelin Agrar)

Otherwise, we have the standard MAN out of the game here. The LOG is without error, but if something does happen, let me know;)

Further planning:
- Matching decals to the engine configuration
- Other tire configurations