Hotfix, Game 0.5.0c / Engine 0.10.0c

Couple of leftover bugs before we move on to work on next update!

• Corporal will unlock Nightmare difficulty
  
• fix placement of vault room switches
  
• fix death sound volume on multiple deaths
  
• fix menu music not looping
  
• fix UI on ultrawide monitors
  
• fix audio-only mods
  
• add command line option to launch windowed (-window)