FREIGHTLINER CASCADIA 2018 V1.10 [FIX] 1.35.X

Update 1.10: adapts the truck for the open beta of version 1.35 and fixes issues introduced by patch 1.35.

Removes an incorrect engine and adds the correct one with matching gearboxes, cleans up textures and models, fixes cabin recognition, adds extra Flow Below mudguards, improves part icons, separates spoilers from the cabs into their own accessories, switches the DD engine sound to the Mercedes one, and fixes various other bugs.