title: Sitecore pipeline on URL with extension
body: <p>I have a processor inserted in the <em>httpRequestBegin</em> pipeline.
  And I have a WebApi controller setup for the url <code>/_api/user/{username}</code></p>
  
  <p>If I invoke this endpoint with a username that doesn't contain a <code>'.'</code> everything works fine. My controller is hit and everything is right and dandy.</p>
  
  <p>However if the username contains a <code>'.'</code> such as an email address the pipeline isn't hit, but the WebApi controller is hit.</p>
  
  <p>Is there some way to make sure the pipeline is invoked even though there is a <code>'.'</code> in the path?</p>