add n-depth inclusion syntax+example

Adding some examples to make sure this doesn't have any yet-unseen hitches:

• {{List of pictures|content;show:menu|size:icon}}
• {{List of song-lists|content;show:menu|content;show:menu|audio}}
  (where the list is a Pointer, the cards in it are also Pointers, and the cards in it are audio files. audio is an imagined view to play audio files :-)
• ??