Initial commit

This is a rough prototype.

It can:
* Start a server
* Accept a connection
* Start XMPP stream
* Initiate TLS
* Sort of authenticate a client. TBD: actually do it aginst a storage.
* Bind a stream
A bit of documentation
New stanza lookup mechanics

Don't rely on inheritance. It doesn't work with deeper inheritance.
Extracted IQ stanza
Parse bare JIDs
Storage stub
Authenticate users against storage
Roster get

This is a stub of a roaster get iq request