update facebox docs (#11014)

* update facebox docs

- Add example for `docker-compose,yaml`
- Add hint to Account page for `MB_KEY`

* ✏️ Tweak

* add information about machinebox/facebox_noavx

* Minor changes

source/_integrations/facebox.markdown

@@ -18,9 +18,30 @@ MB_KEY="INSERT-YOUR-KEY-HERE"
 
 sudo docker run --name=facebox --restart=always -p 8080:8080 -e "MB_KEY=$MB_KEY"  machinebox/facebox
 ```
+
+or using `docker-compose`:
+
+```yaml
+version: '3'
+services:
+  facebox:
+    image: machinebox/facebox
+    container_name: facebox
+    restart: unless-stopped
+    ports:
+      - 8080:8080
+    environment:
+      - MB_KEY=${MB_KEY}
+      - MB_FACEBOX_DISABLE_RECOGNITION=false
+```
+
 You can run Facebox with a username and password by adding `-e "MB_BASICAUTH_USER=my_username" -e "MB_BASICAUTH_PASS=my_password"` but bear in mind that the integration does not encrypt these credentials and this approach does not guarantee security on an unsecured network.
 
-If you only require face detection (number of faces) you can disable face recognition by adding `-e "MB_FACEBOX_DISABLE_RECOGNITION=true"` to the `docker run` command.
+After you created an account at [Machinebox](https://machinebox.io/account), you can grab your `MB_KEY` at [your Account page](https://developer.veritone.com/machinebox/overview).
+
+If you only require face detection (number of faces) you can disable face recognition by adding `-e "MB_FACEBOX_DISABLE_RECOGNITION=true"` in the `docker run` command.
+
+If your host machine does not support [AVX](https://en.wikipedia.org/wiki/Advanced_Vector_Extensions) and you experience issues running the `machinebox/facebox` image there is an alternative image without AVX support available at `machinebox/facebox_noavx`(*HINT*: This image is currently not supported by machinebox and should only be used if necessary) 
 
 ## Configuration