Could not install package 'Microsoft.Extensions.DependencyInjection.Abstractions 2.0.0 : <p>I'm attempting to use Net Core in my mvc application for security policies. Articles I've read said I need to install DependencyInjection which I'm doing through NuGet in VS 2017.  I'm getting the following error:</p>

<p>Could not install package 'Microsoft.Extensions.DependencyInjection.Abstractions 2.0.0'. You are trying to install this package into a project that targets '.NETFramework,Version=v4.5.2', but the package does not contain any assembly references or content files that are compatible with that framework. </p>

<p>Is this version too new for .net 4.5.2?  What version should I be using?</p>
