title: Group by in DataTable
body: <p>I have a data table:</p>
  
  <pre><code>DataTable table = new DataTable();
  
  table.Columns.Add("Name", typeof(string));
  table.Columns.Add("Value", typeof(string));          
  
  table.Rows.Add("A", "High");
  table.Rows.Add("B", "Low");
  table.Rows.Add("A", "Low");
  table.Rows.Add("C", "High");
  table.Rows.Add("B", "Medium");
  table.Rows.Add("A", "High");
  table.Rows.Add("A", "High");
  </code></pre>
  
  <p>I want to use LINQ to group my result like:</p>
  
  <pre><code>Name   value  Count
  -------------------
  A      High    3
  A      Low     1
  B      Medium  1
  B      Low     1
  C      High    1
  </code></pre>