Use a set instead of a map to reduce needless memory overhead
Use a set instead of a map to reduce needless memory overhead

mapbox/tippecanoe,joykuotw/tippecanoe,mapbox/tippecanoe,mapbox/tippecanoe,joykuotw/tippecanoe,landsurveyorsunited/tippecanoe,landsurveyorsunited/tippecanoe,mapbox/tippecanoe