Update 1.40b: Extreme HUD + new options

[CHANGELOG]
- Add: New difficulty option - Extreme HUD -> Turn off all other HUD user interfaces
- Add: New difficulty option - Teammates vision
- Add: Voices volume option
- Add: New skin camo
- Improve: Leaning slightly system
- Improve: NVG brightness in first-person view
- Improve: Skin camo rendering
- Fix: Rotation error of camera after use of drone/photo mode