update Smack dependency

[rasputnik]

Hi, we run an ejabberd - based XMPP service, and there appears
to be a known issue with Smack 3.1.0 authenticating against it.

Would it be possible to bring your smack dependency up to 3.2.1 ?
(I'd send a pull request, but I don't see any tests in the project so thought
it was safer just to suggest it for now and see what you thought).

The lein string would change to : org.igniterealtime.smack/smack "3.2.1".

Thanks!

[vbauer]

👍