anchor.diff:  To enable sessions in your application you must have a {@link io.vertx.ext.web.handler.SessionHandler}
   on a matching route before your application logic.
   
  -The session handler handles the creation of session cookies and the lookup of the session so you don't have to do
  +The session handler handles the creation of session cookies and the lookup of the session, so you don't have to do
   that yourself.
   
   Sessions data is saved to a session store automatically after the response headers have been sent to the client.
  
positive.code: As the session is stored in the Cookie, this means sessions survive server crashes too.
  
  A second known implementation is the Redis session store. This store works just like the normal cluster store, however
  just like it's name suggests, it uses a redis backend to keep the session data centralized.
  
  Also, there is the Infinispan session store (details below).
  
  
negative.code: 
  The session handler will ensure that your session is automatically looked up (or created if no session exists)
  from the session store and set on the routing context before it gets to your application handlers.
  
  By default, the session handler will always add a session cookie to the HTTP response, even if the session has not been
  accessed by your application. To create the session cookie only when the session has been used, use
  `sessionHandler.setLazySession(true)`.
  
  === Using the session
  
  