docs: function getActions ( ) {
  
          // Determine the events to bind. IE11 implements pointerEvents without
          // a prefix, which breaks compatibility with the IE10 implementation.
          return window.navigator.pointerEnabled ? {
                  start: 'pointerdown',
                  move: 'pointermove',
                  end: 'pointerup'
              } : window.navigator.msPointerEnabled ? {
                      start: 'MSPointerDown',
                      move: 'MSPointerMove',
                      end: 'MSPointerUp'
                  } : {
                      start: 'mousedown touchstart',
                      move: 'mousemove touchmove',
                      end: 'mouseup touchend'
                  };
      }