docs(prometheus-exporter): add README and sample compose setup

prometheus-exporter/support/compose.yml

@@ -0,0 +1,31 @@
+services:  
+  grafana:
+    image: grafana/grafana-oss
+    container_name: factorio_grafana
+    restart: unless-stopped
+    ports:
+      - 3000:3000
+    volumes:
+      - ./grafana/config:/etc/grafana/provisioning/datasources:ro
+      - factorio_grafana:/var/lib/grafana:Z
+
+  prometheus:
+    image: prom/prometheus
+    container_name: factorio_prometheus
+    restart: unless-stopped
+    volumes:
+      - factorio_prometheus:/prometheus:Z
+      - ./prometheus/config:/etc/prometheus:ro
+
+  sidecar:
+    image: httpd:latest
+    container_name: factorio_prometheus_sidecar
+    restart: unless-stopped
+    volumes:
+      - ~/.factorio/script-output:/usr/local/apache2/htdocs:ro
+
+volumes:
+  factorio_grafana:
+    external: true
+  factorio_prometheus:
+    external: true