addons: Update Prometheus from v2.1.0 to v2.2.0

* Annotate Prometheus service to scrape metrics from
Prometheus itself (enables Prometheus* alerts)
* Update kube-state-metrics addon-resizer to 1.7
* Use port 8080 for kube-state-metrics
* Add PrometheusNotIngestingSamples alert rule
* Change K8SKubeletDown alert rule to fire when 10%
of kubelets are down, not 1%
  * https://github.com/coreos/prometheus-operator/pull/1032

addons/prometheus/exporters/kube-state-metrics/service.yaml

@@ -15,5 +15,5 @@ spec:
   ports:
     - name: metrics
       protocol: TCP
-      port: 80
+      port: 8080
       targetPort: 8080