Update CHANGELOG-EE.md for 8.15.3-ee

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CHANGELOG-EE.md

 Please view this file on the master branch, on stable branches it's out of date.
 
+## 8.15.3 (2017-01-06)
+
+- Disable LDAP permission override in project members edit list.
+- Perform only one fetch per push on Geo secondary nodes.
+
 ## 8.15.2 (2016-12-27)
 
 - No changes.

changelogs/unreleased-ee/1475-disable-project-members-ldap-override.yml

----
-title: Disable LDAP permission override in project members edit list
-merge_request:
-author:

changelogs/unreleased-ee/geo-fetch-repo-once.yml

----
-title: Perform only one fetch per push on Geo secondary nodes
-merge_request:
-author: