def next_working_day(count = 1)
      return self if count == 0
      negative = count < 0
      count = count.abs
      date = negative ? yesterday : tomorrow
      
      loop do
        count -= 1 if date.working_day?
        return date if count.zero? 
        
        date += (negative ? -1 : 1).day
      end
    end
def next_working_day(count = 1)
      return self if count == 0
      negative = count < 0
      count = count.abs
      date = negative ? yesterday : tomorrow
      
      loop do
        count -= 1 if date.working_day?
        return date if count.zero? 
        
        date += (negative ? -1 : 1).day
      end
    end
Returns the next (or count'th) working day