title: File extension showing up after pretty URL rewrite
body: <p>I have a rewrite rule like so:</p>
  
  <pre><code>RewriteRule ^listings/?(.*)$ listings.php?slug=$1 [L]
  </code></pre>
  
  <p>I will have URLs like "site.com/listings/Awesome-Place-Or-Thing".  I would like <code>slug</code> to contain "Awesome-Place-Or-Thing" for this URL.  With the current rule, I get:</p>
  
  <pre><code>var_dump($_GET);
  
  'slug' =&gt; string '.php/Awesome-Place-Or-Thing'
  </code></pre>
  
  <p>How do I get rid of the ".php/"?</p>