Feature negotiation, can appear as direct child to Iq or as child of IqSi
First <x/> child with xmlns='jabber:x:data'
# File lib/xmpp4r/feature_negotiation/iq/feature.rb, line 19 def x res = nil each_element('x') { |e| res = e if e.namespace == 'jabber:x:data' } res end