Added somewhat generic nod-exporter and cadvisor playbooks.

roles/cadvisor/templates/cadvisor.service

@@ -0,0 +1,22 @@
+[Unit]
+Description=Prometheus container monitoring.
+After=docker.service
+Requires=docker.service
+
+[Service]
+TimeoutStartSec=0
+Restart=always
+ExecStartPre=-/usr/bin/docker kill %n
+ExecStartPre=-/usr/bin/docker rm %n
+ExecStart=/usr/bin/docker run --name %n \
+    --volume=/:/rootfs:ro \
+    --volume=/var/run:/var/run:rw \
+    --volume=/sys:/sys:ro \
+    --volume=/var/lib/docker/:/var/lib/docker:ro \
+    --volume=/dev/disk/:/dev/disk:ro \
+    --publish=8181:8080 \
+    google/cadvisor:latest
+
+
+[Install]
+WantedBy=multi-user.target