code: public void write(OutputStream out, Integer indent) throws TransformerException {
  		write(out, indent, null);
  	}
docs: Writes the xCal document to an output stream.
  @param out the output stream to write to (UTF-8 encoding will be used)
  @param indent the number of indent spaces to use for pretty-printing or
  "null" to disable pretty-printing (disabled by default)
  @throws TransformerException if there's a problem writing to the output
  stream