Version 0.1.3 rel

Changes and fixes:

• The cursor is no longer locked in the window area. The window can now be minimized and resized.
  
• The calculator cannot be dragged outside the screen.
  
• FPS is locked within 60 frames.
  
• Vertical synchronization has been added.
  
• The appearance of the cursor has been changed.
  
• Sound settings have been added.
  
• Settings are also located in the pause menu during the game session.
  

Balance changes:

• You cannot have more than one charge on the legendary button.
  

New features:

• New button: "Unknown number" - When pressed, it is used as one number, but then changes to another.
  
• New button: "Square" - Raises a number to the power of two.