Merge branch 'update_changelog' into 'master'

Update changelog

keep in mind that there is unmerged MR without updating changelog https://dev.gitlab.org/gitlab/gitlab-ee/merge_requests/268

See merge request !269

CHANGELOG-EE

@@ -2,6 +2,8 @@ v 7.6.0
   - Added Audit events related to membership changes for groups and projects
   - Added option to attempt a rebase before merging merge request
   - Dont show LDAP groups settings if LDAP disabled
+  - Rebase on merge request. Introduced merge request option to rebase before merging
+  - Better message for failed pushes because of git hooks
 
 v 7.5.3
   - Only set up Sidetiq from a Sidekiq server process (fixes Redis::InheritedError)