def define_request_level(name, &block)
      level = RequestLevel.new(name, self)
      level.instance_eval &block
      @levels ||= {}
      @levels[name] = level
    end
def define_request_level(name, &block)
      level = RequestLevel.new(name, self)
      level.instance_eval &block
      @levels ||= {}
      @levels[name] = level
    end
Define a request level for this class
 Takes a name, and a block which defined the request level