Univention Corporate Server 4.1 erratum 173 (bugfix)

This update addresses the following issue(s):
* The synchronization of the password hashes was implemented by using a 
  service which was installed on the Microsoft Active Directory server. The
  Univention AD Connector now uses different interfaces of the Active
  Directory for reading and writing the password hashes. That means, the UCS
  AD Connector service which is installed on the Microsoft Active Directory
  server can be stopped after installing this update.
* If a user was moved on UCS side, the group cache wasn't always updated and
  an error occurred. This issue has been fixed.
* The AD Connector is now restarted after rotating the connector's log files.