I18n: Update translation ca (100%).

387 translated messages.

Transifex (https://www.transifex.com/projects/p/xfce/).
I18n: Update translation ast (93%).

363 translated messages, 24 untranslated messages.

Transifex (https://www.transifex.com/projects/p/xfce/).
I18n: Update translation cs (74%).

290 translated messages, 97 untranslated messages.

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