Since 3.2, Revert property can be set to one of the value of {@link TDraggableRevertOption} enumeration.
o 'True' or 'Revert' : The draggable will revert to it's original position
o 'False' or 'None' : The draggable won't revert to it's original position
o 'Failure' : The draggable will only revert if it's dropped on a non droppable area
