Add watchtower, fixes and prepare for new caddy handling

gitea/docker-compose.yml

@@ -4,6 +4,8 @@ services:
   server:
     image: gitea/gitea:1.17
     container_name: gitea
+    labels:
+      com.centurylinklabs.watchtower.enable: true
     env_file:
     - .env
     - .secret.env
@@ -16,6 +18,14 @@ services:
       - "3000:3000"
       - "3022:22"
       - "22:22"
+    networks:
+      services:
+        aliases:
+          - gitea
 
 volumes:
   data:
+
+networks:
+  services:
+    external: true