code: function(leftScrollElm, rightScrollElm, elmToScroll, scrollSpeed) {
          var scrollSpeed = scrollSpeed ? scrollSpeed : 5;
  
          leftScrollElm.on('mouseenter', function() {
              var timer = setInterval(function() {
                  elmToScroll.scrollLeft(elmToScroll.scrollLeft() - scrollSpeed);
              }, 20);
  
              leftScrollElm.on('mouseleave', function() {
                  clearInterval(timer);
              });
          });
          rightScrollElm.on('mouseenter', function() {
              var timer = setInterval(function() {
                  elmToScroll.scrollLeft(elmToScroll.scrollLeft() + scrollSpeed);
              }, 20);
  
              rightScrollElm.on('mouseleave', function() {
                  clearInterval(timer);
              });
          });
      }
docs: These are real private methods. A plugin instance has access to them
  @return {[type]}
   Method that bind left & right scroll to any scrollable element