Added project license and license notices at the beginnings of the files.

NOTICE

@@ -0,0 +1,10 @@
+jCloud Third-Party Notices
+===========================
+
+This software uses the following third-party libraries. Full license texts are available in the 'licenses/' directory.
+
+1. cryptography 46.0.5
+   Author: Python Cryptographic Authority
+   License: Apache License 2.0
+   URL: https://cryptography.io/
+   See licenses/cryptography.txt for full license text.