func (e *Envelope) AddHeader(name string, value string) error {
	if name == "" {
		return fmt.Errorf("Provide non-empty header name")
	}

	e.header.Add(name, mime.BEncoding.Encode("utf-8", value))
	return nil
}
func (e *Envelope) AddHeader(name string, value string) error {
	if name == "" {
		return fmt.Errorf("Provide non-empty header name")
	}

	e.header.Add(name, mime.BEncoding.Encode("utf-8", value))
	return nil
}
func ( e * Envelope ) AddHeader ( name string , value string ) error { if name == " " { return fmt . Errorf ( " " ) } e . header . Add ( name , mime . BEncoding . Encode ( " " , value ) ) return nil }
// AddHeader appends given header value to header name without changing existing values.
// If the header does not exist already, it will be created.
AddHeader appends given header value to header name without changing existing values . If the header does not exist already it will be created .