In order to get a better look-up experience (images, description,
redirects, and disambigutation pages listed last), swich from
a custom title-autocomplete input (that used jquery.suggestions)
to OOUI's standard one (which is used in a bunch of other places
in MediaWiki).
This means a fair bit of code can be deleted from
jquery.wikiEditor.dialogs.config.js, and some of it moved to
the new OOUI classes.
This patch aims to be the minimum required, and so leaves a few
things for subsequent patches (such as converting the other parts
of the insert-link dialog to OOUI).
Bug: T289214
Change-Id: I9fb7e66bf925eb9a8260d6245d2a7db54a7a2fec
