title: LINQ OrderBy custom order
body: <p>Say I have the following character array:</p>
  <pre><code>char[] c = new char[] { 'G', 'R', 'D', 'D', 'G', 'R', 'R', 'C', 'D', 'G', 'R', 'R', 'C', 'G', 'R', 'D', 'D', 'G', 'R', 'R', 'C', 'D', 'G', 'R', 'R', 'C' };
  
  
  c.OrderBy(y =&gt; y).ForEach(x =&gt; Console.WriteLine(x));
  //CCCCDDDDDDGGGGGGRRRRRRRRRR
  </code></pre>
  <p>How do I use LINQ to produce the following order?</p>
  <pre><code>//DDDDDDGGGGGGRRRRRRRRRRCCCC
  </code></pre>