Add the ability to restore hue and saturation from the original image.

[jxxxxst]

Your commits break this extension for me. Here is the error log:

    RuntimeError: The size of tensor a (4) must match the size of tensor b (3) at non-singleton dimension 0

Update: Fixed & created a pull request for you: https://github.com/jxxxxst/stable-diffusion-webui-pixelization