[Documentation] Add binding + debug tool (#960)

* add tools

* put latest version first

Author: JosephChotard

Diff for: website/docs/community/applications.md

@@ -11,3 +11,4 @@ The following applications use H3. Contributions to this list are welcome, pleas
 
 - [kepler.gl](http://kepler.gl/) - An open source geospatial analysis tool
 - [pydeck](https://deckgl.readthedocs.io/) - High-scale spatial rendering in Python, powered by deck.gl
+- [h3-viewer](https://h3.chotard.com/) - Debugging tool to visualise h3 on mercator projection, powered by deck.gl

Diff for: website/docs/community/bindings.md

@@ -137,4 +137,6 @@ As a C library, bindings can be made to call H3 functions from different program
 
 ## Spark
 
-- [kevinschaich/h3-pyspark](https://github.com/kevinschaich/h3-pyspark)
+- [jchotard/h3spark](https://github.com/JosephChotard/h3spark) (4.x)
+- [kevinschaich/h3-pyspark](https://github.com/kevinschaich/h3-pyspark) (3.x)
+