Merge branch 'testing'

Squashed commit of the following:

commit ce55b800
Author: Benedikt Wegmann <benedikt.wegmann@gwdg.de>
Date:   Thu Jun 23 10:56:26 2016 +0200

    docker: FIX

commit 422cfc9f
Author: Benedikt Wegmann <benedikt.wegmann@gwdg.de>
Date:   Thu Jun 23 10:55:41 2016 +0200

    docker: FIX

commit a42c828f
Author: Benedikt Wegmann <benedikt.wegmann@gwdg.de>
Date:   Thu Jun 23 10:53:42 2016 +0200

    docker: FIX

commit eb00a72b
Author: Benedikt Wegmann <benedikt.wegmann@gwdg.de>
Date:   Thu Jun 23 10:51:47 2016 +0200

    docker: FIX

commit 210c0972
Author: Benedikt Wegmann <benedikt.wegmann@gwdg.de>
Date:   Thu Jun 23 10:46:22 2016 +0200

    docker

unattended_upgrades: ${distro_id}:${distro_codename}-updates aus Template in Konfiguration verschoben

This reverts commit 26a8c683.