def configure(*val , &block)
      case val.size
      when 1
        return @config[val[0]]
      when 2
        @config[val[0]] = val[1]
        instance_variable_set("@#{val[0]}", val[1]) 
      end
      instance_eval &block if block_given?
    end
def configure(*val , &block)
      case val.size
      when 1
        return @config[val[0]]
      when 2
        @config[val[0]] = val[1]
        instance_variable_set("@#{val[0]}", val[1]) 
      end
      instance_eval &block if block_given?
    end
might as well add more keys for paging.