title: facebook graph api logout after fetching profile details
body: <p>I am implementing "login with facebook" feature using <strong>php sdk</strong>, i am able to grab user profile details. But after that user remains logged in. Suppose user is accessing my site and after using "login with facebook" features he leaves immediately, then next person sitting there can use(misuse) previous persons account. 
  1)How can i automatically logout user after fetching what i needed (I dont want to show user "facebook logout" button).
  2) Is there any way i can only logout user from my app and not facebook logout ? (i mean if user is already using facebook in another tab then it should only logout users facebook session from my app.)</p>