title: Generate GUID from a string that is not in guid format
body: <p>I would like to generate a GUID from the input string. Let's say I have guid received from the user which is </p>
  
  <pre><code>81a130d2-502f-4cf1-a376-63edeb000e9f
  </code></pre>
  
  <p>so I can do:</p>
  
  <pre><code> Guid g = Guid.Parse("81a130d2-502f-4cf1-a376-63edeb000e9f");
  </code></pre>
  
  <p>which is going to parse successfully.</p>
  
  <p>But how to make user's life easier and allow to input:</p>
  
  <pre><code>81a130d2502f4cf1a37663edeb000e9f
  </code></pre>
  
  <p>which is without dashes, and still convert it to guid.</p>
  
  <p>If I will try to use the same method it's gonna throw the exception complaining on the missing dashed in the guid format. </p>
  
  <p>Any ideas?</p>