title: NLog trace target only works right for trace and debug levels, not info, warn, error, or fatal
body: <p><sub>Please note I am answering my own question to help people in the future.</sub></p>
  
  <p>When I use NLog to log to a trace target type, it only works correctly if the level is <code>Trace</code> or <code>Debug</code>.  If it's <code>Info</code>, <code>Warn</code>, or <code>Error</code>, it prepends extra info before my layout.  If the level is <code>Fatal</code>, I get a pop-up complaining about a failed assertion and it says so in the output too.  Is the trace target bugged?</p>
  
  <p><strong>Program.cs</strong></p>
  
  <pre><code>using System;
  
  namespace TraceLoggingTest
  {
      class Program
      {
          private static NLog.Logger logger = NLog.LogManager.GetCurrentClassLogger();
  
          static void Main(string[] args)
          {
              logger.Trace("Hello Trace");
              logger.Debug("Hello Debug");
              logger.Info("Hello Info");
              logger.Warn("Hello Warn");
              logger.Error("Hello Error");
              logger.Fatal("Hello Fatal");
  
              Console.ReadLine();
              NLog.LogManager.Shutdown();
          }
      }
  }
  </code></pre>
  
  <p><strong>NLog.config</strong></p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8" ?&gt;
  &lt;nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://www.nlog-project.org/schemas/NLog.xsd NLog.xsd"
        autoReload="true"
        throwExceptions="false"
        internalLogLevel="Off" internalLogFile="c:\temp\nlog-internal.log"&gt;
  
    &lt;targets&gt;
      &lt;target name="logTrace" xsi:type="Trace" layout="${message}" /&gt;
    &lt;/targets&gt;
  
    &lt;rules&gt;
      &lt;logger name="*" minlevel="Trace" writeTo="logTrace" /&gt;
    &lt;/rules&gt;
  &lt;/nlog&gt;
  </code></pre>
  
  <p><strong>Expected output</strong></p>
  
  <pre><code>Hello Trace
  Hello Debug
  Hello Info
  Hello Warn
  Hello Error
  Hello Fatal
  </code></pre>
  
  <p><strong>Actual output</strong></p>
  
  <pre><code>Hello Trace
  Hello Debug
  TraceLoggingTest.exe Information: 0 : Hello Info
  TraceLoggingTest.exe Warning: 0 : Hello Warn
  TraceLoggingTest.exe Error: 0 : Hello Error
  ---- DEBUG ASSERTION FAILED ----
  ---- Assert Short Message ----
  Hello Fatal
  ---- Assert Long Message ----
  </code></pre>