Modified record and zone class to support IDN
    
    * Records data are always returned as string
    * Attributes idnsname, idnssoamname, idnssoarname are returned as
    * DNSName, with
      option --raw as string
    * option --raw returns all IDN domains punycoded
    
    Part of ticket:
    IPA should allow internationalized domain names
    https://fedorahosted.org/freeipa/ticket/3169
    
    Reviewed-By: Jan Cholasta <jcholast@redhat.com>