Module to expire user accounts.

This module can be used to expire user accounts. Expired users receive
an Access-Reject on every authentication attempt. Expiration is based
on the Expiration attribute which should be present in the check item
list for the user we wish to perform expiration checks.



Expiration attribute format:

You can use Expiration := "23 Sep 2004" and the user will 
no longer be able to connect at 00:00 (midnight) on September 23rd, 
2004.  If you want a certain time (other than midnight) you can do 
use  Expiration := "23 Sep 2004 12:00".
The nas will receive a Session-Timeout attribute calculated to kick
the user off when the Expiration time occurs.



Example entry (users files):

user1	Expiration := "23 Sep 2004"
