Balance update

Story mode has become more difficult.

• Increases enemy's vision
  
• Increases the HP of enemies and bosses in Story Mode
  
• Nerf repeater skill cooldown
  
• Decrease the knockback rate for the arrow
  

Convenience enhancements

Players feedback has been reflected.

• Windowed mode window support
  
• V-SYNC support (optional)
  
• Sound volume control support