title: Adding EventLog as target in NLog for .NET Core app causes Parsing configuration error
body: <p>I have a .NET Core Console app where I use NLog.
  When I try to add EventLog as target in the nlog.config the load of the configuration failes with the following: </p>
  
  <blockquote>
    <p>System.ArgumentException: Target cannot be found: 'EventLog'.</p>
  </blockquote>
  
  <p>I have found a similar question in stackoverflow: 
  <a href="https://stackoverflow.com/questions/51615831/nlog-not-writing-to-eventlog-net-core-2-1">NLog not writing to eventlog .NET Core 2.1</a>. And the suggested solution is to add the Nuget-package NLog.WindowsEventLog which I have. And the version I have downloaded is 4.5.10 so it should not have the bug in v. 4.5.7 mentioned in the other stackoverflow post. And it still does not work.</p>
  
  <p>Here is some information:</p>
  
  <ul>
  <li>BCL: .NETCore.App (2.1.2)</li>
  <li>Dependencies from NLog: 
  
  <ul>
  <li>NLog (4.5.10)</li>
  <li>NLog.Extensions.Logging (1.3.0)</li>
  <li>NLog.WindowsEventLog (4.5.10)</li>
  </ul></li>
  </ul>
  
  <p>And here is the nlog.config:</p>
  
  <pre class="lang-xml prettyprint-override"><code>&lt;?xml version="1.0" encoding="utf-8" ?&gt;
  &lt;!-- XSD manual extracted from package NLog.Schema: 
  https://www.nuget.org/packages/NLog.Schema--&gt;
  &lt;nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd" 
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        autoReload="true"
        internalLogFile="logs\internal-log.log"
        internalLogLevel="Trace" &gt;
  
       &lt;!-- the targets to write to --&gt;
        &lt;targets&gt;
            &lt;target xsi:type="EventLog" name="eventlog" source="testlogging" 
  log="Application" layout="${message}" /&gt;
        &lt;/targets&gt;
  
    &lt;!-- rules to map from logger name to target --&gt;
    &lt;rules&gt;
      &lt;logger name="*" minlevel="Trace" writeTo="eventlog" /&gt;
    &lt;/rules&gt;
  &lt;/nlog&gt;
  </code></pre>
  
  <p>Have I missed something?</p>