Update HACK.md

Signed-off-by: Alex Young <alex@heuris.io>

contrib/HACK.md

@@ -9,7 +9,7 @@ $ ./build.sh
 
 Now edit the gateway service in your `docker-compose.yml` file and deploy the stack.
 
-If you want to use an overriden name then pass in the tag to the `./build.sh` script such as `./build.sh test-1`.
+If you want to use an overridden name then pass in the tag to the `./build.sh` script such as `./build.sh test-1`.
 
 ## Hack on the UI for the API Gateway
 
@@ -22,14 +22,20 @@ $ docker stack rm func
 $ docker network create func_functions --driver=overlay --attachable=true
 ```
 
-Now edit the `docker-compose.yml` file and add an attribute to the `functions` network of `attachable`.
+Now edit the `docker-compose.yml` file and replace the existing networks block with:
+
+```
+networks:
+    functions:
+        external:
+            name: func_functions
+```
 
 Now you can run the gateway as its own container and bind-mount in the HTML assets.
 
 ```
-$ cd faas
 $ docker run -v `pwd`/gateway/assets:/root/assets -v "/var/run/docker.sock:/var/run/docker.sock" \
--p 8080:8080 --network=func_functions -ti functions/gateway:latest-dev
+-p 8080:8080 --network=func_functions -itd functions/gateway:latest-dev
 ```
 
-Now deploy the rest of the stack with:  `./deploy_stack.sh`.
+Now deploy the rest of the stack with: `./deploy_stack.sh`.