anchor.diff:  }
   
   Returns the currently submitted fields and material filenames and size, this is the only interface giving back the complete submission status
  -GET /submission/<submission_id>
  +GET /submission/{submission_id}
   < 200
   < Content-Type: application/json
   {
  
positive.code: ]
  
  Upload a file to the selected tip. Returns a JSON array with file information.
  POST /tip/<tip_id>/file
  > Content-Disposition: attachment; filename="1375888134.png"
  > Content-Length: 43271
  > Content-Type: image/png
  
negative.code: ]
  
  Returns all the comments for a specified tip
  GET /tip/{receipt_id}/comments
  > X-Session: session_id
  < 201
  [
  