code: def order(field = nil, &block)
        if block_given?
          @collection = @collection.sort{|o1, o2| yield(o1, o2)}
        else
          raise ArgumentError.new('you must supply a field name to sort unless you supply a block.') if field.nil?
          @collection = @collection.sort{|o1, o2| o1.send(field) <=> o2.send(field)}
        end
        self
      end
docs: Specifies how to sort. only ascending sort is supported in the short
   form. For descending, implement the block form.
  
       Task.where(:name).eq('bob').order(:pay_grade).all  => array of bobs ascending by pay grade
       Task.where(:name).eq('bob').order(:pay_grade){|o1, o2| o2 <=> o1}  => array of bobs descending by pay grade