Improving German translation and introducing correct line breaks

Improved one translation for Save -> Speichern instead Archivieren
Fixed one type Date instead of Datei
And fixed the linebreaks in label1.Text in FormGitReview that were wrong when I saved them in the translation tool and instead displayed as special characters on the Label.
![GitExtensions_Fixed_Edit_gitreview_page](https://f.cloud.github.com/assets/3082683/241166/a906d006-8993-11e2-8ddc-e2e4fe0dfec5.png)