code: function getConfig(context, options, extendsDefaults) {
    const defaults = getDefaults(context, options);
    const config = $.config(options, defaults, (typeof extendsDefaults !== `boolean`) || extendsDefaults);
    config.metadata = { global: config.metadata, collections: {
      'error-pages': {
        pattern: `**/{500,404}.*`,
        metadata: {
          permalink: false
        }
      }
    }};
    return config;
  }
docs: Gets postprocessed config.
  
  @param {Object} context
  @param {Object} options
  @param {boolean} extendsDefaults
  
  @return {Object}