I18n: Remove broken / unsupported translations.

See http://users.xfce.org/~nick/broken-i18n/ for files and logs.

Use https://www.transifex.com/projects/p/xfce/ to upload fixed versions or request a translation team.
I18n: Add new translation nl (100%).

681 translated messages.

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

681 translated messages.

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

681 translated messages.

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

681 translated messages.

Transifex (https://www.transifex.com/projects/p/xfce/).
I18n: Add new translation en_AU (100%).

681 translated messages.

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