code: protected String punct(final Parse punct, final int i) {
      final StringBuilder feat = new StringBuilder(5);
      feat.append(i).append("=");
      feat.append(punct.getCoveredText());
      return feat.toString();
    }
docs: Creates punctuation feature for the specified punctuation at the specified
  index based on the punctuation mark.
  
  @param punct
  The punctuation which is in context.
  @param i
  The index of the punctuation with relative to the parse.
  @return Punctuation feature for the specified parse and the specified
  punctuation at the specfied index.