Declare remote data field

1. Allow specifying a "dataField" to extract JSON. 

    This is needed when dealing with JSON APIs that always return a root object, even for Arrays. Similarly, it's needed if the API returns a root object because it also needs to return some "meta" data, like pagination. e.g.,

    ```json
    {
      "meta": {
        "page": 1,
        "totalPages": 42
      },
      "results": [
        {
          // The actual search result object
          "name": "Superman",
          "description": "The Man of Steel"
        },
        //...
      ]
    }
    ```


1. Remove a couple of unused copies of the `css` and `js` file from the `example` directory.