title: Case insensitive replace all
body: <p>I am looking for any implementation of case insensitive replacing function. For example, it should work like this:</p>
  
  <pre><code>'This iS IIS'.replaceAll('is', 'as');
  </code></pre>
  
  <p>and result should be:</p>
  
  <pre><code>'Thas as Ias'
  </code></pre>
  
  <p>Any ideas?  </p>
  
  <p><strong>UPDATE:</strong>  </p>
  
  <p>It would be great to use it with variable:</p>
  
  <pre><code>var searchStr = 'is';
  'This iS IIS'.replaceAll(searchStr, 'as');
  </code></pre>