* the XML specification.
   *
   * <p>This escaper does not escape non-ASCII characters to their numeric character references
   * (NCR). However, horizontal tab {@code '\t'}, line feed {@code '\n'} and carriage return {@code
   * '\r'} are escaped to a corresponding NCR {@code "&#x9;"}, {@code "&#xA;"}, and {@code "&#xD;"}