title: Error trying to run mstest on jenkins
body: <p>I´m trying to configure MSTest build plugin on jenkins, but I´m getting the following error:</p>
  
  <pre><code>Path To MSTest.exe: mstest.exe
  Result file was not found so no action has been taken. file:/C:/Program%20Files%20(x86)/Jenkins/jobs/SoftwrenchvNext/workspace/TestResult.trx
  FATAL: null
  java.lang.NullPointerException
      at org.jenkinsci.plugins.MsTestBuilder.perform(MsTestBuilder.java:144)
  </code></pre>
  
  <p>The configuration simply specifies TestResult.trx as ResultFileName. This file is not versioned, and I expect it to be created on each build.</p>
  
  <p>What needs to be done for that?</p>