Reference: https://bl.ocks.org/mbostock/5593150
https://github.com/mapzen/d3-vector-tiles/blob/gh-pages/topojson.html https://github.com/tilezen/vector-datasource https://122e4e-mapbox.global.ssl.fastly.net/mapbox-gl-js/example/third-party/
https://d3js.org/d3.v4.min.js
https://d3js.org/d3-tile.v0.0.min.js