Fix alarm playlist paging doesn't work

The LMS documentation states that:
The "alarm playlists" returns all the playlists, sounds, favorites etc. available to alarms.

This will however return only one playlist: the current playlist.
Inspection of the LMS code reveals that the "alarm playlists" command takes the
customary <start> and <itemsPerResponse> parameters, but these are interpreted as
categories (eg. Favorites, Natural Sounds etc.), but the returned list is flattened,
i.e. contains all items of the requested categories.

So we order all playlists like below, hoping there are no more than 99 categories.
cli.requestItems("alarm playlists", 0, 99, callback);