xmpp.client.PlugIn:
Common xmpppy plugins infrastructure: plugging in/out,
debugging.
xmpp.auth.Bind:
Bind some JID to the current connection to allow router know of
our location.
xmpp.auth.NonSASL:
Implements old Non-SASL (JEP-0078) authentication used in
jabberd1.4 and transport authentication.
xmpp.commands.Command_Handler_Prototype:
This is a prototype command handler, as each command uses a disco method
and execute method you can implement it any way you like, however this is
my first attempt at making a generic handler that you can hang process
stages on too.
xmpp.session.Session:
The Session class instance is used for storing all
session-related info like credentials, socket/xml stream/session
state flags, roster items (in case of client type connection)
etc.