Order presented editions by edition id
Order presented editions by edition id

Make sure the editions that are returned by the export for a document
are always ordered in ascending order by edition id. This ordering is
important as we use it to create a sequential list of editions in
content-publisher ->
https://github.com/alphagov/content-publisher/blob/master/lib/whitehall_importer/import.rb#L31.

alphagov/whitehall,alphagov/whitehall,alphagov/whitehall,alphagov/whitehall