anchor.diff:  the web interface is the most practical way of scrolling them.)
   
   Cues can also be triggered from simpler MIDI controllers (which
  -don&rsquo;t register as grid controllers) by explicitly mapping notes
  +don't register as grid controllers) by explicitly mapping notes
   or control changes sent by the controller to cues within the grid
   using
   http://deepsymmetry.org/afterglow/doc/afterglow.show.html#var-add-midi-control-to-cue-mapping[afterglow.show/add-midi-control-to-cue-mapping].
  
positive.code: http://deepsymmetry.org/afterglow/doc/afterglow.effects.cues.html#var-cue[cue]
  function creates a cue. At its most basic, you pass in two parameters,
  `show-key` which is the keyword that will be used to add the
  cue&rsquo;s effect to the show when the cue is triggered, ending any
  other effect running under that same keyword, and `effect`, which is a
  function that will be called when the cue is triggered, and whose
  responsibility is to create and return the effect that the cue should
  
negative.code: To trigger a cue, simply press the corresponding pad on a physical
  interface, or click within the grid cell in the web interface. The
  effect associated with the cue will be created and added to the show,
  and the grid cell will be lightened to indicate that the cue's
  effect is running. If the cue ends itself after a period, the grid
  interface will be updated to reflect that as well.
  
  To end a cue's effect before it would naturally end (or because
  it is open-ended and does not end until asked to), simply press the
  pad corresponding to the running cue (or, again, click the grid cell
  in the web interface). The effect will be asked to end. Some effects
  