Univention Corporate Server 4.2 erratum 158 (bugfix)

This update addresses the following issue(s):
* IPv6 addresses are now handled correctly and all available
  IP addresses of a system are written to the portal entry
  (beforehand, only the default IP addresses were used).
* Container passwords aren't changed anymore during container upgrades.
* If the download of App meta data via zsync fails, the archive is downloaded
  via an HTTPS request