code: function foldline(aLine) {
      var result = "";
      var line = aLine || "";
  
      while (line.length) {
        result += ICAL.newLineChar + " " + line.substr(0, ICAL.foldLength);
        line = line.substr(ICAL.foldLength);
      }
      return result.substr(ICAL.newLineChar.length + 1);
    }
docs: Performs iCalendar line folding. A line ending character is inserted and
  the next line begins with a whitespace.
  
  @example
  SUMMARY:This line will be fold
  ed right in the middle of a word.
  
  @param {String} aLine      The line to fold
  @return {String}           The folded line