Add `id` attributes to settings section to allow to open if an hash is provided in the URL
In this MR https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/13991/diffs we introduced the possibility of linking to an hash and expand the section linked.
In order to make it possible for all sections, each needs to have a unique identifier with the hash.
.settings#js-unique-id
No JavaScript is required for this issue, only HTML.
/cc @iamphill