German translation for 5.3

Change-Id: I9f98b3d81085ced53837cda00c41136a93197c08
Reviewed-by: Robert Loehning <robert.loehning@digia.com>
Reviewed-by: Christian Stenger <christian.stenger@digia.com>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>