Making a "maximize selection" button and a ratio indicator

In the particular use story where I need the Manual Crop module, the users need to select how the fixed-ratio crops of their article images are being cropped. Therefore, they don't necessarily need crop anything away, but just want to adjust the area which is used for the fixed-ratio crops.

I found it a little bothersome to drag a selection right from the edge of the image or moving it in place.

Therefore, I made this patch, which adds a "Maximize selection" button, that selects the entire image but also respects the aspect ratio if set in the image style settings.