Better support for touch

- Bigger touch targets for cropper handles
- Better touch support detection for IE
Added preventSelectionFlipping flag

If preventSelectionFlipping is set to true, selection will not be
flipped after passing the zero point.
Fixed maxSize / setSelect() conflict

If maxSize was specified, setSelect() with a bigger than max region
would prevent free move of the selection for the first time user
attempts to move (all consecutive moves will succeed though). This fix
ensures that x2/y2 coordinates are constrained properly after
setSelect() call.
Max size must be scaled if aspect ratio isn't 1:1
Updated minimized version.