Merge changes from topics "quantizer_improved_logic", "reintroduce_scaling_fixes" into sc-dev

* changes:
  Quantize image to 128 colors instead of 5
  Quantizer improvements
  Sort colors from high count => low count
  Don't interpolate image input to quantizer
  Cache set wallpaper as PNG instead of JPEG
  Only rescale wallpaper if its > display height