title: Implement Custom AuthenticationHandler in CQ5
body: <p>I want to have a remote system to do the user authentication for our CQ5. I'm guessing AuthenticationHandler on a path is the direction to go. If so, how does AuthenticationHandler works in general. And, In CQ5, how I implement a Custom AuthenticationHandler? How do I go about making it an OSGi bundle (or fragment bundle) and install it into CQ5?</p>
  
  <p>If possible, some code sample with OSGi manifest is appreciated.</p>