Add suspend permission; don't let admins be suspended

extensions/suspend/js/admin/src/main.js

@@ -1,6 +1,12 @@
 import { extend } from 'flarum/extend';
 import app from 'flarum/app';
+import PermissionGrid from 'flarum/components/PermissionGrid';
 
 app.initializers.add('suspend', () => {
-  // TODO
+  extend(PermissionGrid.prototype, 'moderateItems', items => {
+    items.add('suspendUsers', {
+      label: 'Suspend users',
+      permission: 'user.suspend'
+    });
+  });
 });