EntityFramework 6.1.3不支持visual studio 2015上的框架.NETPlatform,Version = v5.4

知道为什么我在Nuget安装Entity framework 6.1.3后收到以下错误？

错误通知:"项目foo栏中的依赖项EntityFramework 6.1.3不支持框架.NETPlatform,Version = v5.4"

这是我的global.json(已编辑的个人数据)

{
  "version": "1.0.0-*",
  "description": foo bar Class Library",
  "authors": [ "foo bar" ],
  "tags": [ "" ],
  "projectUrl": "",
  "licenseUrl": "",
  "frameworks": {
    "net451": { },
    "dotnet5.4": {
      "dependencies": {
        "Microsoft.CSharp": "4.0.1-beta-23516",
        "System.Collections": "4.0.11-beta-23516",
        "System.Linq": "4.0.1-beta-23516",
        "System.Runtime": "4.0.21-beta-23516",
        "System.Threading": "4.0.11-beta-23516"
      }
    }
  },
  "dependencies": {
    "EntityFramework": "6.1.3"
  }
}