I18n: Update translation ar (95%).

262 translated messages, 11 untranslated messages.

Transifex (https://www.transifex.com/projects/p/xfce/).
I18n: Update translation tr (95%).

262 translated messages, 11 untranslated messages.

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