This requires an extra credential for SASL authentication:
xmpp = ClientXMPP('user@chat.facebook.com', '...access_token...')
xmpp.credentials['api_key'] = '...api_key...'
The mechanism name was being correctly de-plussed, but then we used the
original, -PLUS, name to extract the hash, finding SHA-1-PLUS and therefore
finding no match.
Test-Information:
Tested with Sleek against an Isode M-Link with SCRAM-SHA-1-PLUS available.
Author: dwd
