Update code to support argument feature

Usage: python cpisign.py -k CPIKEY example1.json example2.json ...
and input the password of CPI key to sign the data

Change-Id: Ieb0183208aab351f907f41d69ec8052cce5cecb7
diff --git a/.reuse/dep5 b/.reuse/dep5
index fe17096..72b0c50 100644
--- a/.reuse/dep5
+++ b/.reuse/dep5
@@ -1,5 +1,5 @@
 Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
 
-Files: VERSION .gitreview README.md
+Files: VERSION .gitreview README.md example.json
 Copyright: 2021 Open Networking Foundation
 License: Apache-2.0