Volvo D11 Engines v1.0

In this mod I added the real D11 Volvo engines series. I've picked up their specs from the official Volvo site. They are intended for VNL, FH16 and FH16 Classic and are meant to be paired with the gearbox from my other mod "24_speed_transmission", otherwise they are too weak.

Updates:

- Compatible with v1.40. Default sounds now work with these engines.

- added some real life engines, other than D11, that work with Aradeth's Volvo VNL 670 mod (also default sounds).

- added support for Lucasi's Volvo F12 mod. If you want his engines, just put his mod in higher priority than this one.

- added Volvo 425V engine to the D11 family.