Code cleanup in SASLMechanism

- typos
- deprecated methods
- whitespace fixes
Don't set SASL authid parameter to username (SMACK-371)

RFC4616 states that if the authorization identity (authzid) parameter is
null, then it is derived from the authentication
identity (authcid). Smack currently sets both, authzid and authcid, to
the username, resulting in auth attempts of

userid\0userid\0password

instead of

userid\0password

Which are different users on most systems (e.g. Kerberos).

We now set only SASLMechanism.authenticationId to username. The
authenticate(String, CallbackHandler) method does now not longer receive
the username, as it's send by the CallbackHandler.
s/XMPPConnection/TCPConnection
Move Jingle packet and provider under smackx.jingle

The Jingle integration-tests where also accidentally not within the
smackx package.
Migrated Roster Item Exchange to new manager design

The finalize approach was flawed anyway, it would have never been
called. Because if the packetListener was still referenced from a
connection, and the connection was still strong referenced, then a
strong reference from a gc root would still exists to the manager, which
would prevent it from being gc'ed and finalized being called.
Move Roster Item Exchange code to legacy project

XEP-93 has been deprecated and superseded by XEP-144.