title: Draggable true in rails map not work?
body: <p>I use gmaps4rails. I instance map in rails and it works but when i pass the atrribute draggable : true the map not work. This is my code .</p>
  
  <pre><code>handler = Gmaps.build('Google');
    handler.buildMap({ provider: {maxZoom: 5}, internal: {id: 'map'}}, function(){
    markers = handler.addMarkers([
          {
            "lat": 22,
            "lng": 22,
            "picture": {
              "width":  32,
              "height": 16
            },
            "infowindow": "hello!",
          },
          {
             "draggable": true
          }
        ]
        );
        handler.bounds.extendWith(markers);
        handler.fitMapToBounds();
        handler.map.centerOn({ lat: 22, lng: 22 })
    });
  </code></pre>