Update advertising_networks.txt

http://forum.adguard.com/showthread.php?783-%D0%90%D0%B4%D1%80%D0%B5%D1%81%D0%B0-%D0%B4%D0%BE%D0%BC%D0%B5%D0%BD%D0%BE%D0%B2-%D1%80%D0%B5%D0%BA%D0%BB%D0%B0%D0%BC%D0%BD%D1%8B%D1%85-%D1%81%D0%B5%D1%82%D0%B5%D0%B9/page6