Redesign admin accounts index (#9340)

* Improve overview of accounts in admin UI

- Display suspended status, role, last activity and IP prominently
- Default to showing local accounts
- Default to not showing suspended accounts

* Remove unused strings

* Fix tests

* Allow filtering accounts by IP mask

config/locales/nl.yml

@@ -123,10 +123,6 @@ nl:
       most_recent_ip: Laatst gebruikt IP-adres
       no_limits_imposed: Geen limieten ingesteld
       not_subscribed: Niet geabonneerd
-      order:
-        alphabetic: Alfabetisch
-        most_recent: Meest recent
-        title: Sorteren
       outbox_url: Outbox-URL
       perform_full_suspension: Opschorten
       profile_url: Profiel-URL