replaced deprecated option /e with callable function

http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=31197


option /e was marked as deprecated since PHP 5.5.0


> ( ! ) Deprecated: preg_replace(): The /e modifier is deprecated, use preg_replace_callback instead in  ~\libraries\joomla\filter\input.php on line 664

regards,
Yurii