title: PackageReference condition is ignored
body: <p>In my VS 2017 project I reference docfx.console package and I want it to be used only when certain condition is met. But the package gets used for all builds. </p>
  
  <p>Here is a part of my project. I want docfx.console to be used when configuration is Installer/AnyCPU and VS is building net40 flavor.</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;Project Sdk="Microsoft.NET.Sdk"&gt;
    &lt;PropertyGroup&gt;
      &lt;TargetFrameworks&gt;net40;netstandard1.3;netstandard2.0&lt;/TargetFrameworks&gt;
      &lt;!-- ... --&gt;
      &lt;Configurations&gt;Debug;Release;Installer&lt;/Configurations&gt;
    &lt;/PropertyGroup&gt;
  
    &lt;ItemGroup Condition=" '$(TargetFramework)'=='net40' "&gt;
      &lt;!-- ... --&gt;
      &lt;PackageReference Include="docfx.console" Version="2.30.0" Condition="'$(Configuration)|$(Platform)'=='Installer|AnyCPU'" /&gt;
    &lt;/ItemGroup&gt;
  
      &lt;!-- ... --&gt;
  &lt;/Project&gt;
  </code></pre>
  
  <p>Is there a way to use docfx.console in Installer build for net40 only?</p>