feat: add container hashmap

examples/compose/compose.yaml

@@ -0,0 +1,18 @@
+name: epoch_postgres_example
+
+services:
+  db:
+    image: postgres
+    restart: unless-stopped
+    volumes:
+      - db_data:/var/lib/postgresql/data
+    environment:
+      - POSTGRES_DB=example
+      - POSTGRES_PASSWORD=secret
+
+    labels:
+      - epoch.manage=true
+      - epoch.service.group=databases
+
+volumes:
+  db_data: