use port and host from config

lib/modules/authenticator/index.js

@@ -40,8 +40,9 @@ class Authenticator {
 
   registerEvents() {
     this.events.once('outputDone', () => {
+      const {port, host} = this.embark.config.webServerConfig;
       this.logger.info(__('Access the web backend with the following url: %s',
-        ('http://localhost:8000/embark?token=' + this.authToken).underline));
+        (`http://${host}:${port}/embark?token=${this.authToken}`.underline)));
     });
 
     this.events.setCommandHandler('api:authorize', (token, cb) => {