Improve Prometheus rules and alerts and Grafana dashboards

* Collate upstream rules, alerts, and dashboards and tune for use
in Typhoon
* Previously, a well-chosen (but older) set of rules, alerts, and
dashboards were maintained to reflect metric name changes

docs/addons/grafana.md

@@ -14,7 +14,8 @@ kubectl port-forward grafana-POD-ID 8080 -n monitoring
 
 Visit [127.0.0.1:8080](http://127.0.0.1:8080) to view the bundled dashboards.
 
-![Grafana Capacity Planning](../img/grafana-capacity.png)
-![Grafana Control Plane](../img/grafana-control-plane.png)
-![Grafana Node View](../img/grafana-node.png)
+![Grafana etcd](../img/grafana-etcd.png)
+![Grafana resources cluster](../img/grafana-resources-cluster.png)
+![Grafana usage cluster](../img/grafana-usage-cluster.png)
+![Grafana usage node](../img/grafana-usage-node.png)