title: Regex Match word by being insensitive to Capital Letters
body: <p>I want to match the word <code>"regex"</code> in a given piece of text irrespective of capital letters.</p>
  
  <p><code>'I like regex a lot.'</code> should match.</p>
  
  <p><code>'I like REGEX a lot.'</code> should match.</p>
  
  <p><code>'I like Regex a lot.'</code> should match.</p>
  
  <p><code>'I like ReGeX a lot.'</code> should match.</p>
  
  <p><code>'I like RegeX a lot.'</code> should match.</p>
  
  <p><code>'I like regexa lot'</code> should not match.</p>
  
  <p><code>'I like regex22 lot'</code> should not match.</p>