docs: function copyPluginAssets(output) {
      var book = output.getBook();
  
      // Don't copy plugins assets for language book
      // It'll be resolved to the parent folder
      if (book.isLanguageBook()) {
          return Promise(output);
      }
  
      var plugins = output.getPlugins()
  
          // We reverse the order of plugins to copy
          // so that first plugins can replace assets from other plugins.
          .reverse();
  
      return Promise.forEach(plugins, function(plugin) {
          return copyAssets(output, plugin)
          .then(function() {
              return copyResources(output, plugin);
          });
      })
      .thenResolve(output);
  }