title: Change login button text Facebook SDK 4.7
body: <p>I've successfully upgraded my facebook SDK to v4.7. However, my previous approach to change the login text isn't working anymore. I used</p>
  
  <pre><code>fb:login_text="Facebook" 
  </code></pre>
  
  <p>attribute in my Facebook's login button previously, and it worked fine. Now, after upgrading to 4.7, it isn't.</p>