Add 'groups' page

src/PageTypes.js

@@ -1,5 +1,6 @@
 /*
 Copyright 2015, 2016 OpenMarket Ltd
+Copyright 2017 Vector Creations Ltd
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -23,4 +24,5 @@ export default {
     RoomDirectory: "room_directory",
     UserView: "user_view",
     GroupView: "group_view",
+    MyGroups: "my_groups",
 };