title: Calling devenv.exe for multiple .vdproj files
body: <p>I have a solution that has multiple vdproj files in it.
  I have created an item group in my build.proj file:</p>
  
  <pre><code>&lt;ItemGroup&gt;
  &lt;SetupProjectFiles Include="$(MSBuildProjectDirectory\**\*.vdproj"&gt;
  &lt;/SetupProjectFiles&gt;
  </code></pre>
  
  <p>
  Now I want to call devenv.exe on each of those?</p>
  
  <pre><code>&lt;Exec Command="devenv.exe %(SetupProjectFiles)"&gt;&lt;/Exec&gt;
  </code></pre>
  
  <p>Doesn't work...anyone have any pointers please?</p>