title: linq group by contiguous blocks
body: <p>Let's say I have following data:</p>
  
  <blockquote>
    <p>Time      Status<br>
    10:00     On<br>
    11:00     Off<br>
    12:00     Off<br>
    13:00     Off<br>
    14:00     Off<br>
    15:00     On<br>
    16:00     On</p>
  </blockquote>
  
  <p>How could I group that using Linq into something like</p>
  
  <blockquote>
    <p>[On, [10:00]], [Off, [11:00, 12:00, 13:00, 14:00]], [On, [15:00, 16:00]]</p>
  </blockquote>