Add use of new libnss-role functions for add and delete system roles.

Change the category in the menu from system to users.

Add the ability to manipulate roles and privileges with multi-word names.

Add check of fields for emptiness in dialog boxes.
Change the titles of the listboxes.
Change buttons text.
Add filename substitution by default when adding a privilege to /etc/role.d/.
Add an introspection file.

Add an expert mode.
Add a simple mode.

Initial commit.