def rw_config(key, value, default_value = nil)
      if value.nil?
        acts_as_authentic_config.include?(key) ? acts_as_authentic_config[key] : default_value
      else
        self.acts_as_authentic_config = acts_as_authentic_config.merge(key => value)
        value
      end
    end
def rw_config(key, value, default_value = nil)
      if value.nil?
        acts_as_authentic_config.include?(key) ? acts_as_authentic_config[key] : default_value
      else
        self.acts_as_authentic_config = acts_as_authentic_config.merge(key => value)
        value
      end
    end
This is a one-liner method to write a config setting, read the config
 setting, and also set a default value for the setting.