make links starting with http open in a new tab

theme/sphinx_rigado_theme/layout.html

@@ -108,4 +108,9 @@
       {% endtrans %}
     {%- endif %}
   </div>
+  <script type="text/javascript">
+    $(document).ready(function() {
+        $("a[href^='http']").attr('target','_blank');
+    });
+  </script>
 {%- endblock %}