title: facebook javascript api get user email
body: <p>I am trying to fetch facebook user email for my app. But when i query the email address is returned as null.
  Forums suggest that the user should grant the email permission to your app. How to make user grant that permission or ask him what fields will he give access to the application.
  I am able to get name but not email from the code below.</p>
  
  <pre><code> FB.api(
      {
        method: 'fql.query',
        query: 'SELECT name, email FROM user WHERE uid='+FB.getSession().uid
      },
      function(response) {
            alert(response[0].name);
  
      }
    );
  </code></pre>