Univention Corporate Server 4.1 erratum 293 (bugfix)

This update addresses the following issue(s):
* Fixed handling of App Settings for Docker Apps that do not use a UCS based
  container.
* If a Docker version of an App is released, but a Non-Docker version is
  installed, this version is not shown (and not installable) by default. If
  the App Center is used from a different system, an update is shown, though.
  This display issue was fixed.
* The initialization of all Apps could result in a traceback for Apps with a
  certain version history.