I18n: Update translation vi (85%).

60 translated messages, 10 untranslated messages.

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

70 translated messages.

Transifex (https://www.transifex.com/projects/p/xfce/).
I18n: Update translation nb (72%).

51 translated messages, 19 untranslated messages.

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

70 translated messages.

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