user settings: Remove reset/meta.loaded logic.

We don't really need to know whether we've loaded
the user-related panels, since we only used `meta.loaded`
for a tiny optimization to avoid a jQuery lookup.

We rely mostly on the list widgets from `list_render`,
and they are smart enough to repopulate themselves
when they're called subsequent times.

static/js/settings_sections.js

@@ -74,7 +74,7 @@ exports.reset_sections = function () {
     settings_profile_fields.reset();
     settings_streams.reset();
     settings_user_groups.reset();
-    settings_users.reset();
+    // settings_users doesn't need a reset()
 };
 
 window.settings_sections = exports;