added detail to changelog

Author: brandonjbjelland

CHANGELOG.md

@@ -6,7 +6,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [2.1.0] - 2017-11-16
 #### Added
-* outputs added for listeners (🍰 @mbolek).
+* outputs added for listeners - these can be useful for ECR integration (🍰 @mbolek).
 * Moved default `alb_protocols` to HTTP to lower barier of entry in getting started.
 
 ## [2.0.0] - 2017-11-06