title: jQuery-iax: Cannot read property 'extension' of undefined
body: <p>I have done almost everything .But getting confused with this one. I want to create auto scroll using jQuery-iax . But whenever I tries to scroll page it gives the error. I am very beginner with it.</p>
  
  <p>here is my code.</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>    &lt;script src="http://code.jquery.com/jquery-1.9.1.js"&gt;&lt;/script&gt;
   &lt;script src="//ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"&gt;&lt;/script&gt;
   &lt;script type="text/javascript" src="assets/js/jquery-ias.js"&gt;&lt;/script&gt;
  
         
  &lt;script&gt;
   $(document).ready(function() {
   $.ias({
   item: '.col-md-3',
   container: '.container',
   next: '.nav a',
   pagination: '.nav',
   delay: 600
   })
   .extension(new IASTriggerExtension({offset: 2}))
      .extension(new IASSpinnerExtension())
      .extension(new IASNoneLeftExtension())
   });
  &lt;/script&gt; </code></pre>
  </div>
  </div>
  </p>