title: Using TreeVew to navigate to different pages
body: <p>I would like to make a <code>Settings</code> window similar to the <code>Options</code> box in VS2012. I expect to write a XAML page for each set of settings. But how do I use a <code>TreeView</code> to choose which XAML page gets shown? Should the XAML page be part of the objects that are loaded in the tree?</p>
  
  <p>(I should say, how do I do this in an MVVM way... if possible.)</p>