Fix conversion of preference value to decimal on Ruby 2.4
Fix conversion of preference value to decimal on Ruby 2.4

imella/spree,vinsol/spree,ayb/spree,vinayvinsol/spree,vinsol/spree,imella/spree,vinayvinsol/spree,ayb/spree,imella/spree,vinsol/spree,ayb/spree,vinayvinsol/spree,vinsol/spree,vinayvinsol/spree,ayb/spree