FK-26 Keep image within bounds of trimmer

While image is being moved or resized ensure that it does not move such that any whitespace appears
inside the image trimmer.

Stop the slider from sliding if it makes the image too small.
FK-26 Disable text selection on dragging

When dragging slider or picture starts, stop all text selection on the page
FK-26 Cancel button closes trimmer

Add a event listener so that the cancel button will close the image trimmer