Special:Preferences: Use OOjs UI
* Change the form to OOUI mode. Tweak some formatting to look better
with this mode. Change various random links to be OOUI buttons.
* Rewrite custom tabs to use OO.ui.IndexLayout instead.
* Update styles and JS enhancements for OOUI widgets.
* Rename ResourceLoader modules so that old skin-specific styles
(from $wgResourceModuleSkinStyles) no longer apply. They tend
to make no sense with the OOUI styling.
Bug: T117781
Change-Id: Ie9396f0146f5020e52710c41e55ec86151ae0095