code: public void storeFlattened(File file) throws IOException {
          BufferedOutputStream out = new BufferedOutputStream(
                  new FileOutputStream(file));
          try {
              storeFlattened(out);
          } finally {
              out.close();
          }
      }
docs: Store all properties, those local and also those in parent props
  
  @param file
  The file to store to
  @throws IOException
  If there is an error writing