Scania 4

Mod tested and working only on 1.12

Changes in v1.6
- Added cistern for BDF with trailer
- New cab for BDF
- Edited chassi for BDF, added few details
- Grill in 3D, you can paint now (select with engine)
- Added seat adjustment
- Added new fuel tank (black)
- Fixed indicator controls in interior
- Fixed wheel index in BDF trailers