Univention Corporate Server 4.1 erratum 131 (bugfix)

This update addresses the following issue(s):
* Some ldap search requests have been optimized in the handler modules.
* In situations where the IP address of a created computer contained two
  equal blocks (e.g. 10.10.20.0/24) invalid pointer records were created.
* The layout of DNS service and text records have been adjusted to be more
  readable.
* It is now prevented to create extended attributes for users with required
  fields without specifying a default value. Those extended attributes caused
  problems during upgrading to UCS 4.1 or installing various apps.
* The search filter for "name" in the dns/dns module now also finds zones and
  pointer records.
* The search filter for "dhcpPermitList" in the dhcp/pool lookup function has
  been fixed.
* The search filter for "fqdn" has been adapted so it can be used to search
  for multiple computers.
* Some columns which show more information in the grid of UMC have been added
  to the DNS handler modules.