Version 2.2.0

• Added more command-line options for resizing textures.
  • width, height, min, and max may be used for the image width, image height, max between width and height, and min between width and height.
  • Can append each of the above options with -nextpo2 and -nearestpo2 for the next and nearest power of two.
  • example: --resize max-nearestpo2 max-nearestpo2 to create a square texture with the nearest power of two of the maximum between the image width and height. (i.e. nearestpo2(max(width, height)))
• Fixed incorrect channels when using the --swizzle command-line arguments. This didn't affect swizzling when using the C++ API.

Resolves #4
Resolves #5