title: Trying to setCellValue on blank cell
body: <p>I am trying to insert text into a blank cell </p>
  
  <pre><code>getRow( 0 ).getCell( 0 ).setCellValue( 'Hat Selection' ) 
  </code></pre>
  
  <p>and I keep getting </p>
  
  <p><em>Cannot invoke method setCellValue() on null object</em></p>
  
  <p>Why can't I insert text into this blank cell? How can I?</p>