Move the crop area with keyboard cursor control keys

It appears that Image Widget Crop does not offer this feature natively.

I move the Feature Request to them.

Being able to set the crop area using keyboard is also very important for accessibility.
Taking a look at this module though, it looks like it makes use of a third party library (cropper.js) for the actual crop functionality.
So making this module keyboard-accessible might require forking or replacing this library entirely.

This is something I need to solve for on a current project, so will post a follow-up if I find a good solution.

I just opened a pull request (#4) with one possible solution for adding keyboard controls, for consideration.
It adds left, right, up, and down buttons for moving the crop selection and "smaller" and "bigger" buttons for resizing the crop selection area.