cheat sheets.

* ajax:before – right before ajax call
* ajax:loading – before ajax call, but after XmlHttpRequest object
  is created)
* ajax:success – successful ajax call
* ajax:failure – failed ajax call
* ajax:complete – completion of ajax call (after ajax:success and
  ajax:failure)
* ajax:after – after ajax call is sent (note: not after it returns)

(credit: http://bu.tt/48m)