Unless otherwise directed by the court, the parties may by written stipulation (1) provide that depositions may be taken before any person, at any time or place, upon any notice, and in any manner and that when so taken may be used like other depositions, and (2) modify other procedures governing or limitations placed upon discovery, except that stipulations extending the time provided in Rules 33, 34, and 36 for responses to discovery may, if they would interfere with any time set for filing of motions, for hearing of a motion, or for trial, be made only with the approval of the court.