is a tool for displaying the CalDAV and CardDAV resources a user is
currently subscribed to via APNS.
should be run as a user with the same privileges as the Calendar
Server itself, as it needs to read data that belongs to the server.
takes a list of userids as arguments and then displays the resources
currently subscribed to, as well as an identifier of the subscribed
device and timestamp of last subscription.
A userid may be specified in record "short name" form.