Updated Volvo sounds to current ets2 version

Added from ETS2 OM471 and OM473 sounds (equivalent to Detroit Diesel DD13 and DD16), added Man TGX E6 D26 and D38 engine sounds (these are equivalent to Navistar Maxxforce 13/N13/A26 and Maxxforce 15/N15)

Note that the added sounds are not accessible until I say so (which mean that for the A26 sound, no engine until SCS add the LT, for the N15, none until someone add the older ProStar or the First Gen Lonestar, and for the DD engines, none until SCS either add Daimler Trucks (Western Star and Freightliner) or until someone point me toward a good mod that could use these)

Now enforcing restrictions for the Volvo VNL combination of engine and transmissions as per Volvo official Specs :

For XE Packages, ONLY i-Shift Transmission in the appropriate ratios as called by Volvo specifications.

For the others, restrictions according to the engine generation (EPA2013 will use transmission using the generation suffix "D", EPA2017 model will use transmission with the generation suffix "F", Also the X15 Efficiency will use the AT2612F and ATO2612F if specced with a i-Shift Transmission, while the Performance version will use the AT2812F and ATO3112F as it was before the Volvo D16 was discontinued)

Restriction should not affect other transmission mod adding new transmissions (such as Loadersaint mod) except for the XE specs

small update for the K100E

Removed Eaton Endurant transmissions, please use Loadersaint transmission mod for those starting from now

Additional 3406E ratings thanks to Smarty! Go check his Wheel packs for really good tires and wheels BTW! And his great Scot A2HD!

Also, take notes that only the International 9800 will have these, for the rests you still have the C-15 and C-16, which are basically rebadged 3406E (BTW, when truckers and enthusiasts talk about the 6NZ and 7CZ, which are often seen as the pinnacles of 3406Es, they talk about the C-15 and C-16)

All done now

Revert to previous version, forgot something

switched back to Kriechbaum sounds for the following engines :
DD Series 60
Cummins ISM/M11/L10
Paccar MX
Paccar PX