ETS2 - Sound Fixes Pack V20.42 (1.38.x)

Version 20.42 Changelog:
Overhaul of grass sounds on grass areas.

Version 20.41:
Silenced air shifting sounds. [ATS edition]

Version 20.40:
Adjusted mix for gravel sounds to correct for changes in 1.38.
Further adjustment of probabilities for default parking brake engage sound with left window open.

Version 20.39:
Adjusted probabilities for default parking brake engage sound with left window open.

Version 20.38.1:
Compatibility update for 1.38 ETS2 open beta.

Authors: * SCS Software for base sounds
* Drive Safely for sound edits, some sound samples, and for compiling mod
* antonvezdehod for high speed tire sound
* Deltatristar500 for an external parking brake sound sample
* Grinch for default railroad crossing bell sound rework
* kriechbaum for light switch sound
* Vasily EVR for some air brake sound samples