title: .gitignore does not work for subfolder of ignored folder
body: <p>I'm using Laravel and the Github program for subversions. In my .gitignore file i type:</p>
  
  <p><code>/vendor</code></p>
  
  <p>My project structure looks like this:</p>
  
  <pre><code>Root
   app
   bootstrap
   public
   vendor
  </code></pre>
  
  <p>And it's all the files in vendor i want to ignore in git. Most of the files works to ignore there with typing /vendor in my .gitignore, but some files don't.</p>
  
  <p>The files that doesn't work are <code>autoload.php - vendor/autoload.php</code></p>
  
  <p>And files in <code>vendor/composer</code> - like:</p>
  
  <pre><code>autoload_classmap.php
  autoload_namespaces.php
  autoload_real.php
  ClassLoader.php
  installed.json
  </code></pre>
  
  <p>What am i doing wrong in my .gitignore file?</p>