Use MapSpaFallbackRoute in ReactServices and demo

Microsoft.AspNet.ReactServices/project.json

@@ -26,7 +26,8 @@
   },
   "dependencies": {
     "Microsoft.AspNet.NodeServices": "1.0.0-alpha7",
-    "Microsoft.AspNet.Mvc.TagHelpers": "6.0.0-rc1-*"
+    "Microsoft.AspNet.Mvc.TagHelpers": "6.0.0-rc1-*",
+    "Microsoft.AspNet.SpaServices": "1.0.0-alpha7"
   },
   "resource": [
     "Content/**/*"

samples/react/ReactGrid/Controllers/HomeController.cs

@@ -1,11 +1,10 @@
-using System.Threading.Tasks;
 using Microsoft.AspNet.Mvc;
 
 namespace ReactExample.Controllers
 {
     public class HomeController : Controller
     {
-        public IActionResult Index(int pageIndex)
+        public IActionResult Index()
         {
             return View();
         }

samples/react/ReactGrid/Startup.cs

@@ -58,9 +58,8 @@ namespace ReactExample
             // Add MVC to the request pipeline.
             app.UseMvc(routes =>
             {
-                routes.MapRoute(
+                routes.MapSpaFallbackRoute(
                     name: "default",
-                    template: "{pageIndex?}",
                     defaults: new { controller="Home", action = "Index" });
             });
         }