Integration test two apps

Use localhost for app_with_roles and 127.0.0.1 for app. Confirm we can
deploy both and the respond to requests. Ensure the proxy is removed
once both have been removed.

test/integration/docker/deployer/app/config/deploy.yml

@@ -23,7 +23,8 @@ asset_path: /usr/share/nginx/html/versions
 deploy_timeout: 2
 drain_timeout: 2
 readiness_delay: 0
-
+proxy:
+  host: 127.0.0.1
 registry:
   server: registry:4443
   username: root