Upload dashboards to https://grafana.com/grafana/dashboards

[arthurlutz]

When seeing the grafana dashboards in the documentation, my reflex was to go look for them on https://grafana.com/grafana/dashboards

Maybe they can be uploaded there ? It makes it easier for users to import them into their grafana (copy/paste the ID on their install).

Without it, I had to go through the three dashboards on github, click on "Raw" and copy & paste the json (which is OK, but longer).