code: function setup() {
    if(Hammer.READY) {
      return;
    }
  
    // find what eventtypes we add listeners to
    Event.determineEventTypes();
  
    // Register all gestures inside Hammer.gestures
    Utils.each(Hammer.gestures, function(gesture){
      Detection.register(gesture);
    });
  
    // Add touch events on the document
    Event.onTouch(Hammer.DOCUMENT, EVENT_MOVE, Detection.detect);
    Event.onTouch(Hammer.DOCUMENT, EVENT_END, Detection.detect);
  
    // Hammer is ready...!
    Hammer.READY = true;
  }
docs: setup events to detect gestures on the document