Filllevel Warning for Harvesters

Filllevel Warning for Harvesters.
Makes signal tone at 50% and 80%.
When the Fill Level has reached 80% the Beakon Lights are activated
Changelog: (1.0.0.1)
Sounds have been added for all manufacturers included in the game.
Changelog: (1.0.0.2)
The warning tones can now be switched on/off (Standart Key K).