Add and use IQReplyFilter (SMACK-533)

In the absence of checks on the from address, it is possible for other
clients to fake an answer to an IQ request.

This commit adds an IQReplyFilter, which drops all packets which are not
a valid reply to an IQ request. In particular, it checks for packet id,
from address and packet type.

Most(?) places waiting for a reply to an IQ request are converted to use
the IQReplyFilter.

For a discussion of the issues, see the thread "Spoofing of iq ids and
misbehaving servers" from 2014-01 on the jdev@jabber.org mailing list
and following discussion in February and March.
Process only requested roster results (SMACK-538)

Prior to this change, Smack processes each RosterPacket (which is not of
type IQ.Type.RESULT) as a roster result.

Any other client on the XMPP network can send such a packet (not only
our server). This allows a malicious party to overwrite our Roster.

This patch changes smack so that a RosterPacket is discarded if it is
not a reply to a roster request.
Unify AndFilter and OrFilter

AndFilter and OrFilter are dual; there is no reason why they should have
differing interfaces.
Remove remainders of non-SASL authentication (SMACK-446)
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.
Rework XMPP Date/Time related code

- Fix "packet.Time is not thread-safe" (SMACK-543)
- Update packet.Time to XEP-0202

Add SDM.supportsFeature(), since this is a pattern that repeats over and
over again in Smack. Also add abstract Manager class, that takes care of
the weak reference to Connection, as this is also a repeating pattern in
Smack.
SMACK-541 Fix of XHTMLExtensionProvider on Android
This fixes issue there on android in XHTMLExtension bodys contained "null" instead of actual xhtml tags
This happened due to difference in XPP implementation in KXmlPullParser (on Android) MXParser (in other cases)
This fix replaces usage of getText method of XPP with restoration of xhtml tags using XPP api.
Advanced Message Processing implementation (XEP-0079)

Fixes SMACK-544
SMACK-53: create VersionProvider and VersionManager

The VersionProvider is used to parse Version IQs. Integration:

	providerManager.addIQProvider("query", Version.NAMESPACE, new VersionProvider());

The VersionManager is used to reply to Version IQs. Integration:

	VersionManger.getInstanceFor(connection).setVersion(
		new Version("App Name", "1.23", "Operating System"));
Remove deprecated constructor for FromMatchesFilter (SMACK-71)
Cleanup texts and comments
Make StringUtils#hash unsynchronized

MessageDigests are not too expensive to create, so there is no
need to muck around with global state.