Use gorilla readMessage and writeMessage instead of just an io.Copy

vendor/github.com/vulcand/oxy/utils/netutils.go

@@ -132,7 +132,7 @@ func RemoveHeaders(headers http.Header, names ...string) {
 }
 
 // Parse the MIME media type value of a header.
-func GetHeaderMediaType(headers http.Header, name string) (string, error)  {
+func GetHeaderMediaType(headers http.Header, name string) (string, error) {
 	mediatype, _, err := mime.ParseMediaType(headers.Get(name))
 	return mediatype, err
 }