Implement a test suite for the XMPP IoT extensions

Create test suite (using Java Junit) to test the implementation of the XEP 0325 and XEP 323  as smack extensions (the work can be based on the tests already present in the library for the other extensions)  code avaliable in branch xmpp-iot-integration:
https://github.com/codavide/Smack/tree/xmpp-iot-integration/smack-extensions/src/test/java/org/jivesoftware/smackx
