code: function isSimple(config) {
    return (
      isObject(config) &&
      !config.hasOwnProperty('linters') &&
      intersection(Object.keys(defaultConfig), Object.keys(config)).length === 0
    )
  }
docs: Check if the config is "simple" i.e. doesn't contains any of full config keys
  
  @param config
  @returns {boolean}