lxmppd -> core -> stanza_dispatch
	requires	"util.stanza"
	requires	"core.usermanager"
	
function init_stanza_dispatcher(session)
	Initialises the stanza dispatcher which handles different stanza according
	to their type and XML namespace, dispatching to required handlers.
	
	iq_handlers["jabber:iq:auth"]
		A list of handlers for "jabber:iq:auth" stanzas -- authentication
		(request) stanzas.
		
		function (stanza)
			If one of username, password and resource are missing then it ????.
			If not, then it validates the credentials and replies with the
			appropriate stanza.
			
	iq_handlers["jabber:iq:roster"]
		A list of handlers for "jabber:iq:roster" stanzas -- roster management
		
		function (stanza)
			Parses the type of stanza for roster management and does what is
			requested (roster retrieval, etc.)
	
	function (stanza)
		Validates the stanza and calls the required handler