Maxwell's puzzling demon v1.2.2

Levels update

• The hint feature is now available in w4.
• Slightly changed 3-18, 3-18?, 3-19 and 3-H.
• Adjusted ?₁₄, ?₂₀, ?₂₁, ?₂₂ and ?₂₃ in w3?.

Other changes

• The animation is no longer performed when redoing.
• Corrected some text.