title: C# : Building or getting latest keeps adding entity 5 to packages while project has been upgraded to 6
body: <p>After having updated a project using Nuget to Entity 6.1.3., this project keeps adding a package for Entity 5.0.0. when Getting latest of that project or when building it.
  I already looked with low-level search (fileseek) but can't find any reference anymore in that project to EF5.
  Already uninstalled the Entity package and reinstalled, but same result.
  What else can I do to compeltely remove any reference to EF5 ?</p>