title: String to dictionary, and back again
body: <p>I working with a string like this:</p>
  
  <pre><code>Norway, true; Sweden, false; England, null; Denmark, false;
  </code></pre>
  
  <p>I'm trying to get that into a <code>Dictionary&lt;string, bool?&gt;</code> so I can work with it, remove items, compare against other stuff. When I'm done, I want to convert the dictionary back to a similar string and save it. </p>
  
  <p>Any ideas?</p>