I18n: Update translation ast (99%).

207 translated messages, 1 untranslated message.

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

208 translated messages.

Transifex (https://www.transifex.com/projects/p/xfce/).
I18n: Update translation vi (63%).

132 translated messages, 76 untranslated messages.

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