v1.1 Update

Hey folks, 
Unfortunately this may be the first and the last devlog of this particular game, because there's little to no activity or downloads, as well as no feedback, but I am still chosing to leave the game in somewhat finished state, so here are the changes:

- Greatly improved perfomance (up to 200% more framerate)
- Optimized game package size (2.5 times smaller)
- Added hotkeys manual 
- New sounds
- Improved sound attenuation
- Updated ghost model
- Updated ghost chase effect
- Better scene lighting
- Difficulty balance
- Exhaust mechanic
- Flashlight sometimes not working properly fixed
- Other minor bug fixes and game tweaks