<kbd><b>{expire_time [hours=...] [minutes=...] [seconds=...] [days=...]}</b></kbd>:<p>

	    Sets the expire-time for this document.<br>
	    hours=int: Add int * 3600 to the expire time<br>
	    minutes=int: Add int * 60 to the expire time<br>
	    seconds=int: Add int to the expire time<br>
	    days=int, months=int, years=int: Guess..<p>

Bugs: It is not possible at the time to set the date
beyond year 2038, since a unix time_t is used.
