Added the new cookbook to the article map

Author: javiereguiluz

cookbook/map.rst.inc

@@ -52,6 +52,7 @@
 
   * :doc:`/cookbook/deployment/tools`
   * :doc:`/cookbook/deployment/azure-website`
+  * :doc:`/cookbook/deployment/heroku`
 
 * :doc:`/cookbook/doctrine/index`