add cadvisor to prometheus server config

templates/conf/prometheus.yml.j2

@@ -355,3 +355,19 @@ scrape_configs:
         regex: '(.*):9323'
         replacement: '${1}'
 {% endif %}
+
+{% if prometheus_cadvisor_exporter_targets is defined %}
+  # cadvisor #
+  - job_name: cadvisor
+    scrape_interval: 30s
+    static_configs:
+      - targets:
+{% for target in prometheus_cadvisor_exporter_targets %}
+        - {{ target }}:8080
+{% endfor %}
+    relabel_configs:
+      - source_labels: [ __address__ ]
+        target_label: instance
+        regex: '(.*):8080'
+        replacement: '${1}'
+{% endif %}