JavaScript API Digitising enhancements

Idea created by rakroydesriuk-esridist Employee on Apr 9, 2010
    1) Use the onMouseDown event for digitising features rather than the onClick event as this is very hit and miss due to the user moving the mouse whilst digitising,

    2) Make the right mouse button undo digitised points whilst digitising.  E.g. left click 30 points for a polygon, right click to undo the last point (as many times as there are points if you like) because you put a point in the wrong place, rather than cancelling the whole polygon.