Add padding option

[masus04]

Sometimes, an application requires images to be cropped in a certain form, let's say a square. If the source image is very different to that form, let's say a 16:9 aspect ratio image, a user may want to crop out instead of in, filling the empty space with some background instead of removing more of their image.

I propose an option in the Crop widget / CropController that enables zooming out of the image or moving the borders of the crop area outside of the image.
The padding color should also be configurable using the Crop widget / CropController.

[masus04]

An example use case for this is creating an avatar image.

[chooyan-eng]

@masus04 Thank you for your proposal. I understand what you are trying to achieve, but honestly speaking, I do not have any idea how I can develop the feature right now. Let me take a time to think about it.