Asp.NetCore1.1版本去掉project.json后如何打包生成跨平台包

services.AddDistributedMemoryCache();
 services.AddSession(b =>
 {
 b.IdleTimeout = TimeSpan.FromMinutes(1);5 b.CookieName = "MySid";
 });

public IActionResult About()
 {
  _logger.LogInformation("这里是About");

  var userInfo = "我的NetCore之Session";
  HttpContext.Session.Set(SessionKey, System.Text.Encoding.UTF8.GetBytes(userInfo));
  ViewData["Message"] = $"读取配置文件Option1节点值：{this._options.Option1}，添加session";
  return View();
 }

public IActionResult Contact()
 {
  var userInfo = string.Empty;
  if (HttpContext.Session.TryGetValue(SessionKey, out var bt))
  {
  userInfo = System.Text.Encoding.UTF8.GetString(bt);
  }

  ViewData["Message"] = string.IsNullOrWhiteSpace(userInfo) ? "Session获取为空" : userInfo;
  return View();
 }

public static class PublicExtensions
 {
 #region ISession扩展

 /// <summary>
 /// 设置session
 /// </summary>
 /// <typeparam name="T"></typeparam>
 /// <param name="session"></param>
 /// <param name="key"></param>
 /// <param name="val"></param>
 /// <returns></returns>
 public static bool Set<T>(this ISession session, string key, T val)
 {
  if (string.IsNullOrWhiteSpace(key) || val == null) { return false; }

  var strVal = JsonConvert.SerializeObject(val);
  var bb = Encoding.UTF8.GetBytes(strVal);
  session.Set(key, bb);
  return true;
 }

 /// <summary>
 /// 获取session
 /// </summary>
 /// <typeparam name="T"></typeparam>
 /// <param name="session"></param>
 /// <param name="key"></param>
 /// <returns></returns>
 public static T Get<T>(this ISession session, string key)
 {
  var t = default(T);
  if (string.IsNullOrWhiteSpace(key)) { return t; }

  if (session.TryGetValue(key, out byte[] val))
  {
  var strVal = Encoding.UTF8.GetString(val);
  t = JsonConvert.DeserializeObject<T>(strVal);
  }
  return t;
 }

 #endregion
 }

public IActionResult About()
 {
  _logger.LogInformation("这里是About");

  //var userInfo = "我的NetCore之Session";
  //HttpContext.Session.Set(SessionKey, System.Text.Encoding.UTF8.GetBytes(userInfo));

  MoUser user = new MoUser();
  HttpContext.Session.Set<MoUser>(SessionKey, user);
  ViewData["Message"] = $"读取配置文件Option1节点值：{this._options.Option1}，添加session";
  return View();
 }

 public IActionResult Contact()
 {
  //var userInfo = string.Empty;
  //if (HttpContext.Session.TryGetValue(SessionKey, out var bt))
  //{
  // userInfo = System.Text.Encoding.UTF8.GetString(bt);
  //}

  //ViewData["Message"] = string.IsNullOrWhiteSpace(userInfo) ? "Session获取为空" : userInfo;

  var user = HttpContext.Session.Get<MoUser>(SessionKey);
  ViewData["Message"] = user == null ? "Session获取为空" : $"昵称：{user.UserName}";
  return View();
 }

<Project Sdk="Microsoft.NET.Sdk.Web">

 <PropertyGroup>
 <TargetFramework>netcoreapp1.1</TargetFramework>
 </PropertyGroup>
 <PropertyGroup>
 <PackageTargetFallback>$(PackageTargetFallback);portable-net45+win8+wp8+wpa81;</PackageTargetFallback>
 </PropertyGroup>
 <ItemGroup>
 <PackageReference Include="Microsoft.ApplicationInsights.AspNetCore" Version="2.0.0" />
 <PackageReference Include="Microsoft.AspNetCore" Version="1.1.1" />
 <PackageReference Include="Microsoft.AspNetCore.Mvc" Version="1.1.2" />
 <PackageReference Include="Microsoft.AspNetCore.Session" Version="1.1.1" />
 <PackageReference Include="Microsoft.AspNetCore.StaticFiles" Version="1.1.1" />
 <PackageReference Include="Microsoft.Extensions.Logging.Debug" Version="1.1.1" />
 <PackageReference Include="Microsoft.VisualStudio.Web.BrowserLink" Version="1.1.0" />
 </ItemGroup>
 <ItemGroup>
 <DotNetCliToolReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Tools" Version="1.0.0" />
 </ItemGroup>
</Project>

 <PropertyGroup>
 <RuntimeIdentifiers>win7-x64;ubuntu.16.04-x64</RuntimeIdentifiers>
 </PropertyGroup>