The default thread count should be reflected on KestrelServerInformation.ThreadCount during application start

[AspNetSmurfLab]

The default thread count is currently determined by KestrelEngine after the application's Conifgure method has been called. This means the application can't inspect the default value for IKestrelServerInformation.ThreadCount, like it can for IKestrelServerInformation.NoDelay. Essentially, the following code should echo the correct defaults:

public void Configure(IApplicationBuilder app)
{
    var kestrel = app.ServerFeatures[typeof(IKestrelServerInformation)] as IKestrelServerInformation;

    if (kestrel != null)
    {
        Console.WriteLine($"Kestrel thread count: {kestrel.ThreadCount}");
        Console.WriteLine($"Kestrel TCP no-delay: {kestrel.NoDelay}");
    }