Merge branch '1118-fix-approvals-api-documentation' into 'master'

Fix Approvals API documentation

Related issue https://gitlab.com/gitlab-org/gitlab-ee/issues/1118

See merge request !846

changelogs/unreleased-ee/1118-fix-approvals-api-documentation.yml

+---
+title: Fix Approvals API documentation
+merge_request: 
+author: 

doc/api/merge_requests.md

@@ -610,7 +610,7 @@ POST /projects/:id/merge_requests/:merge_request_id/approve
   "updated_at": "2016-06-09T21:32:14.105Z",
   "merge_status": "can_be_merged",
   "approvals_required": 2,
-  "approvals_missing": 0,
+  "approvals_left": 0,
   "approved_by": [
     {
       "user": {