make renderablezorder::operator sort using signed integers in seamonkeys mode
make renderablezorder::operator sort using signed integers in seamonkeys mode

ccdevnet/openc2e,bdonlan/openc2e,crystalline/openc2e,crystalline/openc2e,ccdevnet/openc2e,bdonlan/openc2e,bdonlan/openc2e,crystalline/openc2e,ccdevnet/openc2e,ccdevnet/openc2e,crystalline/openc2e,ccdevnet/openc2e,bdonlan/openc2e,ccdevnet/openc2e,crystalline/openc2e