title: Sort array items in PHP so that it is not case sensitive to letters
body: <p>When I use <code>sort($topics)</code> I get something along the lines of:</p>
  
  <ol>
  <li>Apple</li>
  <li>Green</li>
  <li>Zebra</li>
  <li>grass</li>
  </ol>
  
  <p>In this example, "grass" starts with a lower case g but ends up after "Zebra" which has a capital letter. </p>
  
  <p>How do I make it so that it sorts it where it ignores whether the word starts with capitals or not?</p>
  
  <ol>
  <li>Apple</li>
  <li>Green</li>
  <li>grass</li>
  <li>Zebra</li>
  </ol>