I18n: Update translation de (75%).

61 translated messages, 20 untranslated messages.

Transifex (https://www.transifex.com/projects/p/xfce/).
I18n: Update translation fr (100%).

81 translated messages.

Transifex (https://www.transifex.com/projects/p/xfce/).
I18n: Update translation pt_BR (100%).

81 translated messages.

Transifex (https://www.transifex.com/projects/p/xfce/).