title: AntiForgery and JSON incompatible?
body: <p>I have been successfully using the AntiForgery option with Ajax in Orchard Modules for a while. Recently, I have been wanting to change from using the default ContentType = 'application/x-www-form-urlencoded; charset=UTF-8' to a JSON payload (ContentType='application/JSON').</p>
  
  <p>As soon as I do this I get an exception thrown by ASP.NET 'A required anti-forgery token was not supplied or was invalid.'. OK, but how do I go about adding the __RequestVerificationToken while preserving JSON payload?</p>
  
  <p>For reference, here is the code I'm using:</p>
  
  <pre><code>    var config = {
          url: url,
          type: "POST",
          data: data ,
          dataType: "json",
          contentType: "application/json; charset=utf-8"
      };
      $.ajax(config);
  </code></pre>
  
  <p>Controller (blows up with 'A required anti-forgery token was not supplied or was invalid.' before it gets here):</p>
  
  <pre><code>    [HttpPost]
      public ActionResult Update(ShoppingCartItemVM[] items)
      {
         // do stuff
      }
  </code></pre>
  
  <p>Is this a limitation of the Orchard AntiForgery wrapper or of the MVC AntiForgery functionality? Or am I being stupid (again)?</p>