title: Is it possible to continue after a fail in a chain?
body: <p>I have something like:</p>
  
  <pre><code>doHTTPRequest()
  .then(handleSuccess, checkNotFound)
  .then(uploadSomething)
  .fail()
  .done()
  </code></pre>
  
  <p>Now when I'm getting into checkNotFound I need to check if I got 404, if so it's not an actual fail and I want to continue with uploadSomething, but Q chaining directs me to fail.
  On any other failure (e.g: any other status code) I do want to get into fail().</p>