code: public static void end(Progression model) {
  		if (model != null) {
  			model.end();
  			model.setComment(null);
  		}
  	}
docs: Force the given task progression, if not <code>null</code>,
  to have its value equals to the maximal value.
  
  <p>The inderterminate and adjusting states are not changed.
  The comment is reset.
  
  @param model is the task progression to initialize.