Merge with changes from master

README.md

@@ -71,6 +71,6 @@ func handleMessage(s xmpp.Sender, p stanza.Packet) {
 }
 ```
 
-## Documentation
+## Reference documentation
 
-Please, check GoDoc for more information: [gosrc.io/xmpp](https://godoc.org/gosrc.io/xmpp)
+The code documentation is available on GoDoc: [gosrc.io/xmpp](https://godoc.org/gosrc.io/xmpp)

stanza/error.go

@@ -23,7 +23,7 @@ func (x *Err) Namespace() string {
 	return x.XMLName.Space
 }
 
-// UnmarshalXML implements custom parsing for IQs
+// UnmarshalXML implements custom parsing for XMPP errors
 func (x *Err) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
 	x.XMLName = start.Name