updating change log

Author: davidtruong

CHANGELOG.md

@@ -16,7 +16,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 - nothing yet
 
 ## [2.2.1](https://github.com/Iterable/iterable-android-sdk/releases/tag/2.2.1)
- _Released on 2017-11-10_
+ _Released on 2017-11-20_
 
 #### Added
 - Added the `updateSubscriptions` function to create to modify channel, list, and message subscription preferences.