private static String unescapeString(String s) {
    if (s == null) {
      return null;
    }
    return s.replaceAll("\\\\\\&", "\\&");
  }
A temporary solution that SPARK 1.2 need to escape '&' with '\&' in its javaOptions.
This is the reverse process that recovers the escaped string.

@param s The string to unescape
@return The original string
app/com/linkedin/drelephant/util/InfoExtractor.java