title: Set lock true for group of cells
body: <p>I'm using closedxml to export excel..</p>
  
  <p>Now i can protect (Lock cell) cell using the following function,</p>
  
  <pre><code>workSheet.Cell(rowIndex,column).Style.Protection.SetLocked(true);
  </code></pre>
  
  <p>I want to set group of cells..
  Is that Possible in closedxml ?</p>