= Application filtering =

You can allow users to select which applications they will receive work for
(by default, they may receive work for any or all applications).

This information is stored in the [ProjectSpecificPrefs project-specific preferences],
and you must provide your own interface for editing it.
Each 'allowed' application is represented by an element <app_id>N</app_id>,
where N is the database ID of the application.
If no <app_id> elements are present, the user may be sent work for any application.