code: public void write(File file, Integer indent) throws TransformerException, IOException {
  		write(file, indent, null);
  	}
docs: Writes the xCal document to a file.
  @param file the file 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 IOException if there's a problem writing to the file
  @throws TransformerException if there's a problem writing the XML