Maxwell's puzzling demon v1.0.2

[h3]Levels update[/h3]

• Fixed 4-12, 4-F and 4-H to prevent unintended solutions.
  
• Changed the layout around 6-13~6-16 in w6 because reaching 6-21 was harder than intended.
  
• Changed 9-7 and 9-8, and swapped their positions to adjust for difficulty.
  
• Adjusted the appearance of some levels. (This does not affect the solution of each puzzle.)
  

[h3]Other changes[/h3]

• The indication of a new tip available has been made more prominent so that players don't miss it.