Return crop rectangle in image coordinates

[tylerwilson]

Since this view controller is used to pick out a section of an image of any size, it would be useful to return the crop rect so that the caller can then cut out the rect (or circle) from the original image. Currently the view controller only cuts out the image in the scaled image, resulting in a potentially lower res image.

[lucasecf]

Hi! I think this is a useful feature, and I'll develop it when having some free time :)