title: How to get path to solution directory from inside app.config
body: <p>I have a file: AppSetting.config in the root folder of my solution.
  In my projects App.Config I want to do the following:</p>
  
  <pre><code>&lt;AppSettings file="&lt;PathToSolutionRoot&gt;\AppSetting.config /&gt;
  </code></pre>
  
  <p>Is there a way to get the <code>&lt;PathToSolutionRoot&gt;</code> somehow and stick it in the AppSettings so it points to the solution root folder?</p>