Fix the notification API usage

apps/files_sharing/api/server2server.php

@@ -94,7 +94,7 @@ class Server2Server {
 				$notification = $notificationManager->createNotification();
 				$notification->setApp('files_sharing')
 					->setUser($shareWith)
-					->setTimestamp(time())
+					->setDateTime(new \DateTime())
 					->setObject('remote_share', $remoteId)
 					->setSubject('remote_share', [$user, trim($name, '/')]);
 

apps/files_sharing/appinfo/app.php

@@ -119,4 +119,9 @@ $manager->registerNotifier(function() {
 	return new \OCA\Files_Sharing\Notifier(
 		\OC::$server->getL10NFactory()
 	);
+}, function() use ($l) {
+	return [
+		'id' => 'files_sharing',
+		'name' => $l->t('Federated sharing'),
+	];
 });