Project restructuring, improved iOS 7 support, updated german translation

I know there are a lot of changes made by me. But in most of the I moved files around to get a better structured project. All other changes improve iOS 7 support. Additionally, I updated the German translation.

(I understand that there may be too many changes for a single pull request to be accepted. I just wanted to let you know of my changes, so you can apply them if you want to ;) )