Add search and links to plugin settings (#4854)

* Show links to plugin views and settings in plugin list and in success message after activating a plugin
* Fix menu highlighting in payment provider settings
* Specify settings_links and navigation_links for built-in plugins
* Add link to payment plugins from payment settings
* Add client-side search and "View only active plugins" for plugins page

src/pretix/plugins/statistics/apps.py

@@ -35,6 +35,9 @@ class StatisticsApp(AppConfig):
         version = version
         category = 'FEATURE'
         description = _("Get a birds-eye view of your event sales with graphical statistics.")
+        navigation_links = [
+            ((_("Orders"), _("Statistics")), "plugins:statistics:index", {}),
+        ]
 
     def ready(self):
         from . import signals  # NOQA