public static String unEscapeString(
      String str, char escapeChar, char charToEscape) {
    return unEscapeString(str, escapeChar, new char[] {charToEscape});
  }
Unescape <code>charToEscape</code> in the string
with the escape char <code>escapeChar</code>

@param str string
@param escapeChar escape char
@param charToEscape the escaped char
@return an unescaped string
common/src/java/org/apache/hive/common/util/HiveStringUtils.java