Fix for Issue #411: preg_replace /e is deprecated in php5.5

spouts/rss/heise.php
spouts/rss/mmospy.php
spouts/rss/prolinux.php
do use deprected preg_replace wit /e parameter. With php5.5 this leads to an abort in update.php
preg_replace with /e parameter need to be replaced by preg_replace_callback.