title: How to replace upper case with lower case using regex?
body: <p>I need to replace upper case letter in variable name with lower case letter and add space</p>
  
  <p>For example:</p>
  
  <p><code>NotImplementedException</code> should be <code>Not implemented exception</code>
  <code>UnhandledException</code> should be <code>Unhandled exception</code></p>