Correct 8.15.0 release date in CHANGELOG-EE.md

[ci skip]

CHANGELOG-EE.md

@@ -4,7 +4,7 @@ Please view this file on the master branch, on stable branches it's out of date.
 
 - Fix 404/500 error while navigating to the 'show/destroy' pages. !993
 
-## 8.15.0 (2017-01-22)
+## 8.15.0 (2016-12-22)
 
 - Adds a check ensure only active, ie. non-blocked users can be emailed from the admin panel.
 - Add user activities API.