Added rating_sum check


git-svn-id: svn://oss.dbc.dk/sync_php/php/OpenLibrary/OpenVoxb/trunk@63872 30e9dc4a-7611-4fbc-83ba-eecf79b76bd0
Fixed conditional


git-svn-id: svn://oss.dbc.dk/sync_php/php/OpenLibrary/OpenVoxb/trunk@63877 30e9dc4a-7611-4fbc-83ba-eecf79b76bd0