I18n: Update translation es (65%).

257 translated messages, 138 untranslated messages.

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

395 translated messages.

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

395 translated messages.

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