title: Equivalent to App.config transforms for .NET Core?
body: <p>I'm writing a .NET Core console application (<strong><em>NOT</em></strong> an ASP.NET Core web application).  In .NET Framework I would have an <code>App.config</code>, and <code>App.Debug.config</code>, and an <code>App.Release.config</code> file, the latter 2 for transforming the former.  This allowed me to change various settings based on whether I was creating a debug or a release build.</p>
  
  <p>Now with .NET Core, you're meant to use <code>appsettings.json</code> instead.  Fine, but how do I do my debug and release transforms with this?  I've read something about using an environment variable to determine whether you're in a release or debug environment but I really don't want to do this and it's not really appropriate for console applications anyway.  So how can I transform config files in a similar way to how it was done in .NET Framework?</p>