Univention Corporate Server 4.0 erratum 44 (bugfix)

This update addresses the following issues:
 * Allows UMC modules to set the response status when the module
   initialization fails. This is required to show the login dialog after a
   password change.
 * UMC identifies now also users without posix account as LDAP users.
 * Fixed a bug which prevented that UMC components could write into their
   logfiles.
 * Fixed handling of crashed UMC module processes.
 * Add the UMCP flavor to error information when a traceback occurs.
 * Connections to the LDAP server weren't closed after the session timeout.
   This caused a UMC server crash due to max open file limits.