Translation update from the SWM community

* Added German translation for new system messages
* Minor changes to existing German translations
* linkfixes

Change-Id: I4af315b9282940ab901b7d0ff0c2cd34bed070fc
Tweaks and changes to several system messages

* amended typography for some messages
* amended one system message (wrong variable usage)
* amended one system message (intended meaning)
* changed one system message to make it more adequate (including a URL-fix)

Change-Id: Ib93c91a1eef4d6c4dffaba8e03a902c67875a8aa