Merge pull request #226 from imo/develop

Correct argument order by using keyword for keepalive.
Add XEP-0196 for User Gaming, from mathieui
Prevent race condition in pubsub test.
Merge branch 'develop' of github.com:fritzy/SleekXMPP into develop
Fix bug where authentication fails because we reply with the wrong realm. By using an empty realm, it will be overridden by the value returned by the server.