Moving a project on disk breaks IntelliSense, etc due to caching of targets

1. Clone https://github.com/Ponant/ResxBugVS2017RC
2. Open project
3. Notice that Dependencies node has errors and get Intellisense errors

I debugged this and this is caused by the caching of the NuGet props, which results in the wrong paths being used for $(ProjectAssetsFile), for example, from a design-time build:
```
17>Target "ResolvePackageDependenciesForBuild" skipped, due to false condition; ('$(ResolvePackageDependenciesForBuild)' == 'true' and Exists('$(ProjectAssetsFile)')) was evaluated as ('true' == 'true' and Exists('U:\Calculus\Visual Studio 2017\Projects\ResBugWebAppCore11\ResBugWebAppCore11\obj\project.assets.json')).
```

This is despite this project being on my D:\. NuGet restore will re-generate the props/targets to point to the correct paths but Visual Studio will not pick up the new values until you restart it.