Improved Exhaust Effects V1.2

Improves the exhaust smoke effects of motorized vehicles: – Darkens the smoke with vehicles without AdBlue – Increased amount of smoke depending on the engine temperature – Enhanced effect when starting the engine v1.1.0: – FIX: Corrected the motor start event causing thick white smoke (or no smoke) after the engine got warm – FIX: Exhaust smoke should no longer be solid white in certain conditions (especially an issue in multiplayer)