title: check if file exists (case-sensitive)
body: <p>Is there a way to check whether a file exists in NodeJS, with case-sensitivity, <em>even when the underlying file system isn't case sensitive</em>?</p>
  
  <p><a href="http://nodejs.org/api/fs.html#fs_fs_exists_path_callback" rel="nofollow">fs.exists()</a> may or may not be case sensitive depending on the underlying file system.</p>
  
  <pre><code> fs = require('fs');
   fs.existsSync('readme.txt') // true
   fs.existsSync('README.TXT') // false (or true, depending on the file system)
  </code></pre>
  
  <p>This causes problems when developing an app on a case-insensitive development environment that will be deployed on a case-sensitive server. I recently had an issue where the build was broken by a typo. It worked locally.</p>
  
  <p>If I can get Node to tell me, "yes, <code>README.TXT</code> exists, and it's stored as <code>readme.txt</code>" that will be enough to solve the problem.</p>