Restore dockerized grafana setup

It's stil on a separate machine, but in docker to allow more applications to be run easier and tied together.

ansible/roles/forrest/files/docker-compose.yml

@@ -0,0 +1,33 @@
+version: "2.3"
+
+services:
+  grafana:
+    image: grafana/grafana:latest
+    environment:
+      - TZ=Europe/London
+      - GF_DATABASE_URL=postgres://grafana:grafana@db/grafana
+      - GF_RENDERING_SERVER_URL=http://renderer:8081/render
+      - GF_RENDERING_CALLBACK_URL=http://grafana:3000/
+    volumes:
+      - ./grafana:/var/lib/grafana
+    restart: unless-stopped
+    ports:
+      - 3000:3000
+    depends_on:
+      - db
+      - renderer
+
+  db:
+    image: postgres:12-alpine
+    restart: unless-stopped
+    volumes:
+      - ./postgres:/var/lib/postgresql/data
+    environment:
+      - POSTGRES_PASSWORD=grafana
+      - POSTGRES_USER=grafana
+
+  renderer:
+    image: grafana/grafana-image-renderer:latest
+    restart: unless-stopped
+    environment:
+      - BROWSER_TZ=Europe/London