title: How to terminate session when the browser is closed in rails 3
body: <p>can somebody tell / show me how to terminate session in rails 3?</p>
  
  <p>In my web app, if the user closed the browser and opened it again the the user is still logged in. How am I gonna make it automatically log out when the user closed the browser? </p>
  
  <p>Pls help.</p>