There's a Rheinland news story that mentions 'the city of Muleheim'. This city doesn't actually exist, but it sounds similar to Mülheim, so it's been changed to that.
This resolves the issue where players with foreign installs will have the blank ship control names. Now they'll at least still be displayed in English, but they can always be translated later. This commit also adds a few missing tool tips for the new controls.
