title: services.AddLogging() prevent NLog logger running?
body: <p>I have the following .net core 2.0 code and the NLog is not output anything.</p>
  
  <pre><code>private static IServiceProvider BuildDi()
  {
      var services = new ServiceCollection();
  
      services.AddTransient&lt;Runner&gt;();
  
      services.AddSingleton&lt;ILoggerFactory, LoggerFactory&gt;();
      services.AddSingleton(typeof(ILogger&lt;&gt;), typeof(Logger&lt;&gt;));
      services.AddLogging((builder) =&gt; builder.SetMinimumLevel(LogLevel.Trace));
  
      var serviceProvider = services.BuildServiceProvider();
  
      var loggerFactory = serviceProvider.GetRequiredService&lt;ILoggerFactory&gt;();
  
      //configure NLog
      loggerFactory.AddNLog(new NLogProviderOptions { CaptureMessageTemplates = true, CaptureMessageProperties = true });
      NLog.LogManager.LoadConfiguration("nlog.config");
  
      return serviceProvider;
  }
  </code></pre>
  
  <p>And it starts to output after the following line is removed?</p>
  
  <pre><code>services.AddLogging((builder) =&gt; builder.SetMinimumLevel(LogLevel.Trace));
  </code></pre>
  
  <p>What is <code>AddLogging</code> for?</p>