Sulk - data - themes - THEMES_INFO

    Themeing info:

A theme directory must contain files following the naming scheme laid out in
the default.  The files square_corridor.png and mini_square.png are read at
runtime to check the scale of the theme.

Other than these two files, if you leave an image out, Sulk will load the image
from the default theme directory instead.

There are the following constraints on themes:

- The 'square' images must all be the same size as square_corridor.png, the 'mini'
  images must all be the same size as mini_square.png, etc etc.

- Image format should respect the transparency method of each file (either
  no transparency, a colorkey keyed to the top left pixel, or an alpha 
  channel).  To check this read load_data() in main.py.

- The ratio between the width of square_corridor.png and mini_square.png must
  be exact, and preferably between 20:1 and 30:1, I'd say.

- The width of mini_square.png must be at least 2 pixels.

- Be careful to make sure odd images like select.png, entry.png, etc 
  are sized in scale.
