Fixes to German translation
Created by: puenka
Among others: Tastatürkürzel -> Tastaturkürzel (typo) (GTK-)Theme -> (GTK-)Thema (as translated in e.g. gnome-tweak-tool)
Created by: puenka
Among others: Tastatürkürzel -> Tastaturkürzel (typo) (GTK-)Theme -> (GTK-)Thema (as translated in e.g. gnome-tweak-tool)