title: What is the process after the Add Token delegate is called in a Stripe iOS implementation?
body: <p>I'm using Stripe and iOS to add payments to my application.</p>
  
  <p>I know I need to submit the token and other information to my server to complete the process, but I'm not sure what to do with the function to show success, dismiss the Stripe controller, and return to my app.</p>
  
  <pre><code>func addCardViewController(_ addCardViewController: STPAddCardViewController, didCreateToken token: STPToken, completion: @escaping STPErrorBlock) {
      self.submitTokenToBackend(token: token, completion: { (error: Error?) in
          if let error = error {
              completion(error)
          } else {
              self.dismiss(animated: true, completion: {
                  //self.showReceiptPage()
                  completion(nil)
              })
          }
      })
  }
  
  func submitTokenToBackend(token: STPToken, completion: (_ error:Error)-&gt;()){
      print("doing this")
  }
  </code></pre>
  
  <p>I'm using Alamofire as my transport engine. </p>