code: function secondsFrom (n, date) {
                      if(typeof date === 'number') date = new Date(date);
                      if(!(date instanceof Date))  date = new Date();
  
                      date.setSeconds(date.getSeconds() + n);
                      return date;
                  }
docs: Advances (or reverses) the date the specified number of days.
  @param {Number} n The number object to operate on.
  @param {Date} date The date to change.
  @return {Date} The modified date.