reacting to HttpAbstractions/pull/455

Author: JunTaoLuo

src/Microsoft.AspNet.Hosting.Server.Abstractions/IServer.cs

@@ -2,7 +2,7 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
-using Microsoft.AspNet.Builder;
+using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Http.Features;
 
 namespace Microsoft.AspNet.Hosting.Server

src/Microsoft.AspNet.TestHost/ClientHandler.cs

@@ -11,7 +11,6 @@
 using System.Net.Http;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.AspNet.Builder;
 using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Http.Features;
 using Microsoft.AspNet.Http.Internal;

src/Microsoft.AspNet.TestHost/WebSocketClient.cs

@@ -8,7 +8,6 @@
 using System.Security.Cryptography;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.AspNet.Builder;
 using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Http.Features;
 using Microsoft.AspNet.Http.Internal;

test/Microsoft.AspNet.Hosting.Tests/WebHostBuilderTests.cs

@@ -4,10 +4,10 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Threading.Tasks;
-using Microsoft.AspNet.Builder;
 using Microsoft.AspNet.Hosting.Fakes;
 using Microsoft.AspNet.Hosting.Internal;
 using Microsoft.AspNet.Hosting.Server;
+using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Http.Features;
 using Microsoft.AspNet.Http.Internal;
 using Microsoft.Extensions.Configuration;