from https://otrs.wikimedia.de/otrs/index.pl?Action=AgentTicketZoom;TicketID=754407:

  * Team field should be longer

  * translation in english

* add title to mail for CENTRAL see https://otrs.wikimedia.de/otrs/index.pl?Action=AgentTicketZoom;TicketID=730829#836131

minor stuff:

* remove dot before "Nextcloud" at login page.

* add Testmode warning at login screen