Add IRC link to website

Author: igorw

source/index.html

@@ -14,6 +14,9 @@ <h1>Stack</h1>
             <li>
                 <a href="https://twitter.com/stackphp"><i class="icon-twitter"></i> @stackphp</a>
             </li>
+            <li>
+                <a href="irc://irc.freenode.net/%23stackphp"><i class="icon-comment"></i> #stackphp</a>
+            </li>
         </ul>
     </p>
 </div>