Add prometheus files (fixes #58)

prom/Dockerfile

@@ -0,0 +1,3 @@
+FROM prom/prometheus
+COPY prometheus.yml /etc/prometheus/prometheus.yml
+

prom/prometheus.yml

@@ -0,0 +1,17 @@
+global:
+  scrape_interval: 1s
+scrape_configs:
+  - job_name: 'prometheus'
+    static_configs:
+      - targets: ['localhost:9090']
+  - job_name: 'node'
+    dns_sd_configs:
+      - names: ['tasks.node']
+        type: 'A'
+        port: 9100
+  - job_name: 'cadvisor'
+    dns_sd_configs:
+      - names: ['tasks.cadvisor']
+        type: 'A'
+        port: 8080
+