Apply changes to multiple dates #146
Description
It often happens that, for example, the room for a course changes permanently or the lecturer starts the course 15 minutes later than scheduled.
It would be nice if you did not have to enter such changes individually for each course event, but could select several at once for which this change should apply. In addition, it could be practical to introduce an option that directly selects all future course events so that you only have to confirm the change.