Handle IBuilder rename to IApplicationBuilder.

src/MusicStore.Spa/Startup.cs

@@ -16,7 +16,7 @@ namespace MusicStore.Spa
 {
     public class Startup
     {
-        public void Configure(IBuilder app)
+        public void Configure(IApplicationBuilder app)
         {
             var configuration = new Configuration()
                 .AddJsonFile("Config.json")

src/MusicStore/Mocks/StartupSocialTesting.cs

@@ -24,7 +24,7 @@ namespace MusicStore
 {
     public class StartupSocialTesting
     {
-        public void Configure(IBuilder app)
+        public void Configure(IApplicationBuilder app)
         {
             Console.WriteLine("Social Testing mode...");
             //Below code demonstrates usage of multiple configuration sources. For instance a setting say 'setting1' is found in both the registered sources, 

src/MusicStore/Startup.cs

@@ -20,7 +20,7 @@ namespace MusicStore
 {
     public class Startup
     {
-        public void Configure(IBuilder app)
+        public void Configure(IApplicationBuilder app)
         {
             //Below code demonstrates usage of multiple configuration sources. For instance a setting say 'setting1' is found in both the registered sources, 
             //then the later source will win. By this way a Local config can be overridden by a different setting while deployed remotely.

src/MusicStore/StartupNtlmAuthentication.cs

@@ -30,7 +30,7 @@ namespace MusicStore
     /// </summary>
     public class StartupNtlmAuthentication
     {
-        public void Configure(IBuilder app)
+        public void Configure(IApplicationBuilder app)
         {
             //Set up NTLM authentication for WebListener like below. 
             //For IIS and IISExpress: Use inetmgr to setup NTLM authentication on the application vDir or modify the applicationHost.config to enable NTLM.