title: jQuery file upload doesn't submit extra parameters
body: <p>I need to use the formData parameter available in the jQuery File Upload control to send additional data to the server on submit.  The default implementation for formData is to invoke a function that grabs all controls in the form and serializes them to an array (using the jQuery serializeArray() method).</p>
  
  <p>I have controls in my form, but when the file is uploaded, I am not getting any additional data.  When I inspect via Fiddler, there is nothing in the request that shows these form fields are being submitted.</p>
  
  <p>Is there something additional that needs to be done to get these to submit?</p>
  
  <p>Btw, these two links discuss formData...</p>
  
  <p><a href="https://github.com/blueimp/jQuery-File-Upload/wiki/Submit-files-asynchronously" rel="noreferrer">https://github.com/blueimp/jQuery-File-Upload/wiki/Submit-files-asynchronously</a>
  <a href="https://github.com/blueimp/jQuery-File-Upload/wiki/Options" rel="noreferrer">https://github.com/blueimp/jQuery-File-Upload/wiki/Options</a>
  ...for this one search the page for formData.</p>
  
  <p>For what its worth, the <code>multipart</code> option is set to true.</p>