A contact from the roster (RFC 6121 jabber:iq:roster).
jabber:iq:roster
The groups the contact belongs to.
The contact's bare JID.
Optional
The contact's display name, when set.
The subscription state (none, to, from, both, remove).
none
to
from
both
remove
A contact from the roster (RFC 6121
jabber:iq:roster).