code: public static boolean isBoolesque(String string) {
      checkNotNull(string);
      assertBoolesque(string);
      return isFalsy(string) || isTruthy(string);
    }
docs: Whether string holds a boolean-like value.  It should equal "0", "1", "true" or "false".  This
  method says nothing about whether the object is true or false.
  
  @param string string to check
  @return true if value is "boolesque", false otherwise
  @throws IllegalArgumentException if parameter is not a boolesque value ("1", "true", "0",
  "false")
  @throws NullPointerException     if parameter is null