Add example of full-page prerendering via a custom action result

samples/misc/Webpack/Startup.cs

@@ -5,6 +5,7 @@ using Microsoft.AspNetCore.SpaServices.Webpack;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 using System.IO;
+using Microsoft.AspNetCore.NodeServices;
 
 namespace Webpack
 {
@@ -14,6 +15,7 @@ namespace Webpack
         public void ConfigureServices(IServiceCollection services)
         {
             services.AddMvc();
+            services.AddNodeServices();
         }
 
         // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.