Add framework v2

Author: wilsonge

index.html

@@ -218,6 +218,7 @@ <h1>Joomla! API Documentation</h1>
                                     <div class="thumbnail"><img src="https://api.joomla.org/images/framework.png">
                                         <div class="caption">
                                             <p>
+                                                <a class="btn btn-large btn-block" href="https://api.joomla.org/framework-2/index.html">Framework 2.x</a>
                                                 <a class="btn btn-large btn-block" href="https://api.joomla.org/framework-1/index.html">Framework 1.x</a>
                                             </p>
                                         </div>