Add merge request creation time to /projects/:id/merge_request/:merge_request_id
Created by: tebeka
The object returned by /projects/:id/merge_request/:merge_request_id does not contain the MR creation time, however you can view it on the web UI.
The reason is that we'd like to know which merge requests are "stuck" by polling on the open ones and sending a daily email with ones older than X days.