code: public boolean isSuccessful() {
  		if (!transmissionCompleted) return false;
  		if (response == null) return true;
  		if (!response.isValidErrorMessage()) return true;
  		return false;
  	}
docs: <p>Returns true if no response packet was received for this notification,
  or if one was received but is not an error-response (ie command 8),
  or if one was received but its status is 0 (no error occurred).</p>
  
  <p>Returns false if an error-response packet is attached and has
  a non-zero status code.</p>
  
  <p>Returns false if an exception is attached.</p>
  
  <p>Make sure you use the Feedback Service to cleanup your list of
  invalid device tokens, as Apple's documentation says.</p>
  
  @return true if push was successful, false otherwise