Univention Corporate Server 4.1 erratum 216 (bugfix)

This update addresses the following issues:
* The code for "flat-mode" replication has been removed.
* The check for a full file system was inverted and has been fixed.
* LDAP objects having a multi-valued RDNs are now handled correctly during a
  rename and move.
* A traceback in failed-LDIF-mode has been fixed.
* The replication module now logs more information in case of an object class
  violation.
* The replication module no longer runs as the user 'root':
  * '/var/lib/univention-directory-replication/' is now owned by the user
    'listener:root'.
  * 'failed.ldif' files are now owned by the user 'listener'.
  * LDAP connections are now made by the user 'listener'.