Beta Gavril D-Series addon by AR162b 0.8.1

After reading a lot about, and gaining interest in, Twin-I-Beam (TIB) and Twin-Traction-Beam (TTB) suspension (and multiple requests) I've added the TTB suspension next to the already included TIB suspension as well.
So now you can crash even faster while going off-road.

- Added regular twin traction beam front suspension
- Added race spec twin traction beam front suspension (wider and taller)
- Added custom symmetrical steering for the race spec TIB & TTB (should decrease bump steer)
- Changed the Oldstyle Basic and the Early prerunner to TTB
- Fixed the Oldstyle 'DeLuxe', it had a modern engine
- Added three Oldstyle Short (D10) configs
- Updated the two barrel carb (thanks @QQŁKA de SOQŁ)