Update CHANGELOG-EE.md for 9.0.6-ee

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CHANGELOG-EE.md

 Please view this file on the master branch, on stable branches it's out of date.
 
+## 9.0.6 (2017-04-21)
+
+- Cache Gitlab::Geo queries. !1507
+- Fix searching for notes with elasticsearch when a user is a member of many projects. !1675
+- Fix 500 error when selecting a mirror user.
+- Fix active user count to ignore internal users.
+
 ## 9.0.5 (2017-04-10)
 
 - Return 404 instead of a 500 error on API status endpoint if Geo tracking DB is not enabled.

changelogs/unreleased-ee/1776-fix-elastic-max-clause-count-again.yml

----
-title: Fix searching for notes with elasticsearch when a user is a member of many
-  projects
-merge_request: 1675
-author:

changelogs/unreleased-ee/1983-geo-enabled-cache.yml

----
-title: Cache Gitlab::Geo queries
-merge_request: 1507
-author:

changelogs/unreleased-ee/29316-can-t-select-a-mirror-user-ee.yml

----
-title: Fix 500 error when selecting a mirror user
-merge_request:
-author:

changelogs/unreleased-ee/fix-user-count-2.yml

----
-title: Fix active user count to ignore internal users
-merge_request:
-author: