Enable ajax block loading in public pages. Bug 1425694

Change-Id: I9c615da0e7efad927a42874676e1e6cde777c61f

htdocs/blocktype/blocktype.ajax.php

@@ -10,6 +10,7 @@
  */
 
 define('INTERNAL', 1);
+define('PUBLIC', 1);
 
 require(dirname(dirname(__FILE__)) . '/init.php');
 require($CFG->docroot.'/blocktype/lib.php');