[COMPONENT][PLUGIN] Move Email and XMPP notification handlers from components to plugins, so they can be disabled

plugins/XMPPNotifications/XMPPNotifications.php

@@ -0,0 +1,45 @@
+<?php
+
+// {{{ License
+
+// This file is part of GNU social - https://www.gnu.org/software/social
+//
+// GNU social is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// GNU social is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with GNU social.  If not, see <http://www.gnu.org/licenses/>.
+
+// }}}
+
+/**
+ * Handle xmpp notifications
+ *
+ * @package  GNUsocial
+ * @category Plugin
+ *
+ * @author    Hugo Sales <hugo@fc.up.pt>
+ * @copyright 2020 Free Software Foundation, Inc http://www.fsf.org
+ * @license   https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
+ */
+
+namespace Plugin\XMPPNotifications;
+
+use App\Core\Event;
+use App\Core\Module;
+
+class XMPPNotifications extends Module
+{
+    public function onAddNotificationTransport(&$form_defs): bool
+    {
+        $form_defs['xmpp'] = $form_defs['placeholder'];
+        return Event::next;
+    }
+}