processone/ejabberd — pull request #328 by flygoast (2014-10-24 17:01:47+00:00)
Title: Return an empty <vCard/> element in an IQ-result when no vCard exists.

According to XEP-0054, if no vCard exists, the server MUST return a stanza
error (which SHOULD be ) or an IQ-result containing an
empty element.

Signed-off-by: Gu Feng