use ghcr for README.md demo

README.md

@@ -14,7 +14,7 @@ Monitors network traffic to containers. If there is traffic, the container runs,
     ```
 2. Start the stack
     ```sh
-    DOCKER_BUILDKIT=1 docker-compose up --build
+    docker-compose up
     ```
     This will create 2 containers that you can reach through a third "lazytainer" container
 3. View the running container by navigating to its web ui at `http://localhost:81`. You should see some information about the container

docker-compose.yaml

@@ -2,8 +2,12 @@ version: "3"
 services:
   lazytainer:
     container_name: lazytainer
-    # image: ghcr.io/vmorganp/lazytainer:master
-    build: .
+    # to build the image yourself:
+    # 1. comment 'image:...'
+    # 2. uncomment 'build: .'
+    # 3. instead of 'docker compose up', run 'DOCKER_BUILDKIT=1 docker-compose up --build'
+    image: ghcr.io/vmorganp/lazytainer:master
+    # build: .
     environment:
       - VERBOSE=true # probably set this to false unless you're debugging or doing the initial demo
     ports: