Univention Corporate Server 4.3 erratum 357 (bugfix)

This update addresses the following issue(s):
* The UDM module "settings/data" was added. It can be used to store
  arbitrary data in LDAP.
* The error messages for the join into an Active Directory domain
  have been improved.
* Check output from slapschema during registration of new schemas for errors.
* The umc_init function does not assume to find the LDAP group objects
  "cn=Domain Admins" and and "cn=Domain Users" as direct children of
  the "cn=groups" container anymore. Instead it searches for them (or their
  localized equivalents, like "Domänen-Admins").