Added introduction, architecture section

Updated license header on new files.

Change-Id: Ic44db303ab935099698f8c6547904802381fce5c
diff --git a/readme.rst b/readme.rst
index 6b25028..b25e5b9 100644
--- a/readme.rst
+++ b/readme.rst
@@ -1,3 +1,8 @@
+..
+   SPDX-FileCopyrightText: © 2020 Open Networking Foundation <support@opennetworking.org>
+   SPDX-License-Identifier: Apache-2.0
+
+
 Documentation Guide
 ===================