Issue #2263351 by jcisio: Replace accidentally removed part of default.settings.php.

sites/default/default.settings.php

@@ -49,6 +49,11 @@
  *
  * @see example.sites.php
  * @see conf_path()
+ *
+ * In addition to customizing application settings through variables in
+ * settings.php, you can create a services.yml file in the same directory to
+ * register custom, site-specific service definitions and/or swap out default
+ * implementations with custom ones.
  */
 
 /**