Only use thunarx_menu_provider_get_file_actions (Bug 10492)

Using thunarx_menu_provider_get_file_actions on both folders and
files allows all the options to display. Using both files_actions
and folder_actions would cause some duplicate entires. This allows
the thunar-archive-plugin to provide the 'create archive' menu
option for folders on the desktop.
I18n: Update translation de (85%).

184 translated messages, 32 untranslated messages.

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