Heatmap plot Packages

- API: [https://epiviz.github.io/epiviz.heatmap.gl/docs/](https://epiviz.github.io/epiviz.heatmap.gl/docs/) - DEMO: [https://epiviz.github.io/epiviz.heatmap.gl/](https://epiviz.github.io/epiviz.heatmap.gl/) - Examples are in the [app/index.html](./app/ind