Update CHANGELOG-EE.md for 8.15.0-ee

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CHANGELOG-EE.md

 Please view this file on the master branch, on stable branches it's out of date.
 
+## 8.15.0 (2017-01-22)
+
+- Adds a check ensure only active, ie. non-blocked users can be emailed from the admin panel.
+- Add user activities API.
+- Add milestone total weight to the milestone summary.
+- Allow master/owner to change permission levels when LDAP group sync is enabled. !822
+- Geo: Improve project view UI to teach users how to clone from a secondary Geo node and push to a primary. !905
+- Technical debt follow-up from restricting pushes / merges by group. !927
+- Geo: Enables nodes to be removed even without proper license. !978
+- Update validates_hostname to 1.0.6 to fix a bug in parsing hexadecimal-looking domain names. !982
+
 ## 8.14.5 (2016-12-14)
 
 - Add milestone total weight to the milestone summary.

changelogs/unreleased-ee/788-geo-nodes-removal.yml

----
-title: 'Geo: Enables nodes to be removed even without proper license'
-merge_request: 978
-author: 

changelogs/unreleased-ee/827-fix-numeric-hostnames-in-gitlab-pages.yml

----
-title: Update validates_hostname to 1.0.6 to fix a bug in parsing hexadecimal-looking
-  domain names
-merge_request: 982
-author: 

changelogs/unreleased-ee/905-geo-clone-ui.yml

----
-title: 'Geo: Improve project view UI to teach users how to clone from a secondary Geo node and push to a primary.'
-merge_request: 905
-author:

changelogs/unreleased-ee/ee-1137-follow-up-protected-branch-users-and-groups-ee.yml

----
-title: Technical debt follow-up from restricting pushes / merges by group
-merge_request: 927
-author:

changelogs/unreleased-ee/feature-user-activities-api.yml

----
-title: Add user activities API
-merge_request: 
-author: 

changelogs/unreleased-ee/group-sync-update-perms.yml

----
-title: Allow master/owner to change permission levels when LDAP group sync is enabled
-merge_request: 822
-author:

changelogs/unreleased-ee/mr-origin-863.yml

----
-title: Adds a check ensure only active, ie. non-blocked users can be emailed from
-  the admin panel
-merge_request: 
-author: