gossip_channel.go
func (c *gossipChannel) GossipUnicast(dstPeerName PeerName, msg []byte) error {
	return c.relayUnicast(dstPeerName, gobEncode(c.name, c.ourself.Name, dstPeerName, msg))
}
func (c *gossipChannel) GossipUnicast(dstPeerName PeerName, msg []byte) error {
	return c.relayUnicast(dstPeerName, gobEncode(c.name, c.ourself.Name, dstPeerName, msg))
}
// GossipUnicast implements Gossip, relaying msg to dst, which must be a
// member of the channel.