code: function mergeOptions(app, config, options) {
    if (utils.isView(options)) options = {};
    var opts = utils.extend({}, config, app.options, options);
    opts.cwd = path.resolve(opts.cwd || app.cwd || process.cwd());
    return opts;
  }
docs: Create options from:
  + `config` - settings passed when registering plugin
  + `app.options` - options set on the instance
  + `options` - options passed when calling a loader method