Smack should not reply with multiple stream types after stream initiation is offered

Description

Instead of replying as described in Example 4 of XEP-95, Smack replies with multiple stream types

<iq id="7dnrX-23" to="lolo@foo.bar/Smack" from="lala@foo.bar/Smack" type="result">
    <si xmlns="http://jabber.org/protocol/si">
        <feature xmlns="http://jabber.org/protocol/feature-neg">
            <x xmlns="jabber:x:data" type="submit">
                <field var="stream-method">
                    <value>http://jabber.org/protocol/bytestreams</value>
                    <value>http://jabber.org/protocol/ibb</value>
                </field>
            </x>
        </feature>
    </si>
</iq>

This is caused by StreamNegotiator, but the real problem is that Smack treats the data form like list-multi, when it is specified a list-single. I can only guess why this is the cause, but it may be related to FaultTolerantNegoiator, which seams like a non-standard way to implement fallback from S5B to IBB.

Reported at http://stackoverflow.com/a/23519620/194894