Added reference to English version

Author: Claudio Ludovico Panetta

themes/vue/layout/index.ejs

@@ -31,7 +31,7 @@
       <li class="delimiter">|</li>
       <li><a href="http://jp.vuejs.org" class="nav-link">日本語</a></li>
       <li class="delimiter">|</li>
-      <li><a href="http://it.vuejs.org" class="nav-link">Italiano</a></li>
+      <li><a href="http://vuejs.org" class="nav-link">English</a></li>
     </ul>
   </div>
   <div class="down"><img src="/images/down.png"></div>