Khimera: Destroy all Monster GIrls version 4.2

No, this is not an April Fool! It's really here! You can now use the tab key when mapping keyboard controls!

(And some other things too)

Version 4.2 - April 1, 2022

• Stage timer is now off by default and can be re-activated in the options menu.
  
• Removed ban on 'tab' as a mappable key.
  
• Fixed point in Mt Afrokupa where it was easy to accidentally backtrack and get stuck in a previous point in the stage.