Provide starter Grafana dashboard

[rigtorp]

In order to provide a better out of the box experience include a good starter Grafana dashboard in this repo. The ones published here https://grafana.com/dashboards have several issues and requires fiddling before they work. This is a barrier of entry when evaluating Prometheus as a monitoring solution.

[beorn7]

This might be addressed by #941 .

[beorn7]

Have you looked at the node-mixin in https://github.com/prometheus/node_exporter/tree/master/docs/node-mixin ? It's still work in progress, but it might already be quite helpful.

[jinleileiking]

node-mixin IS EXCELLENT!!! SO GOOD!

[discordianfish]

While it's still work in progress, it exists :) So let's close this issue and track missing bits in separate issues if needed.