Update CHANGELOG-EE.md for 9.5.5-ee

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CHANGELOG-EE.md

 Please view this file on the master branch, on stable branches it's out of date.
 
+## 9.5.5 (2017-09-18)
+
+- [FIXED] Fixes activation of project mirror when new project is created. !2756
+- [FIXED] Geo - Whitelist LFS requests to download objects on a secondary node. !2758
+- [FIXED] Fix unsetting credentials data for pull mirrors. !2810
+- [FIXED] Fix a regression breaking projects with an empty import URL. !2824
+- [FIXED] Fix a 500 error in the SSH host keys lookup action. !2827
+- [FIXED] Ensure #route_setting is available before calling it. !2908
+- [FIXED] Fix branch name regex not saving in /admin/push_rule config.
+- [FIXED] Fix the gap in approvals in merge request widget.
+- [FIXED] Fix merges not working when project is not licensed for squash.
+- Don't put the password in the SSH remote if using public-key authentication. !2837
+
 ## 9.5.4 (2017-09-06)
 
 - [FIXED] Validate branch name push rule when pushing branch without commits. !2685

changelogs/unreleased-ee/3232-lfs-files-pull-from-secondary.yml

----
-title: Geo - Whitelist LFS requests to download objects on a secondary node
-merge_request: 2758
-author:
-type: fixed

changelogs/unreleased-ee/3233-project-mirror-not-actually-active-when-new-project-is-created-fix.yml

----
-title: Fixes activation of project mirror when new project is created.
-merge_request: 2756
-author:
-type: fixed

changelogs/unreleased-ee/3288-fix-repository-mirroring-when-url-is-empty-string.yml

----
-title: Fix a regression breaking projects with an empty import URL
-merge_request: 2824
-author:
-type: fixed

changelogs/unreleased-ee/3312-fix-500-in-ssh-host-keys-action.yml

----
-title: Fix a 500 error in the SSH host keys lookup action
-merge_request: 2827
-author:
-type: fixed

changelogs/unreleased-ee/37197-approved-gap.yml

----
-title: Fix the gap in approvals in merge request widget
-merge_request:
-author:
-type: fixed

changelogs/unreleased-ee/fix-pull-mirror-setting-nil.yml

----
-title: Fix unsetting credentials data for pull mirrors
-merge_request: 2810
-author:
-type: fixed

changelogs/unreleased-ee/sh-fix-admin-push-regex.yml

----
-title: Fix branch name regex not saving in /admin/push_rule config
-merge_request:
-author:
-type: fixed

changelogs/unreleased-ee/sh-fix-api-exception-handling.yml

----
-title: 'Ensure #route_setting is available before calling it'
-merge_request: 2908
-author:
-type: fixed

changelogs/unreleased-ee/sh-fix-squash-when-not-licensed.yml

----
-title: Fix merges not working when project is not licensed for squash
-merge_request:
-author:
-type: fixed

changelogs/unreleased-ee/sh-fix-ssh-mirrors.yml

----
-title: Don't put the password in the SSH remote if using public-key authentication
-merge_request: 2837
-author: