Add <error/> stanza.

src/xmpp/stanza.go

@@ -48,3 +48,8 @@ type Presence struct {
 	To string `xml:"to,attr,omitempty"`
 	From string `xml:"from,attr,omitempty"`
 }
+
+// XMPP <error/> stanza.
+type Error struct {
+	XMLName xml.Name `xml:"error"`
+}

src/xmpp/xmpp.go

@@ -115,6 +115,8 @@ func (x *XMPP) receiver() {
 
 		var v interface{}
 		switch start.Name.Local {
+		case "error":
+			v = &Error{}
 		case "iq":
 			v = &Iq{}
 		case "message":