TODO

TODO
----
- make raise_on_error default to True
- tests resolveHostPort caching
- Iq request  -> query., maybe get fancier

- Important
   - Descriptors instead of property for ElementWrapper _*etAttr and
     _*etChildText
   - Respond to disco#info
       - Disco support... particularly when a mixin is constructed and added to
         a stream the streams DiscoMixin/map should be updated to reflect that
         the new mixin is suported (jabber:iq:version, etc.)
   - Respond to version
   - Respond to ping
   - Remove callback methods that are not async (connectionFailed is the
     same as the exceptions raised by ClientStream.connect, e.g.). Rethink...
     use asyncio.Event???
   - Application signal handers, might help cancelling pending tasks (cleanup)
   - SSL Context options, lock down, cert vaildation, etc.
   - vcard img hashes in presence, http://www.xmpp.org/extensions/xep-0153.html

- Useful
   - time out Stream stanza queue entries
   - Allow "by" attributes on stanza errors.
   ~ bind errors
   - jabber:iq:register via stream:feature (also legacy, which is currently
     implemented)

- Meh
   - jabber:iq:auth via stream:feature (not legacy)
   - Ability to do TLS with immediate handshake (443, 5223, etc.)


Public Servers
---------------
   - jabber.iitsp.com - Openfire  (web registration)
   - lightwitch.org - Metronome   (web registration)