title: Git does not detect folder named with "icon"
body: <p>In my git repository, I have folder name <code>icon</code> folder but git does not track the folder. I have created a new folder with same content named <code>icons</code> and it works fine. Here is the screenshot:</p>
  
  <p><a href="https://i.stack.imgur.com/yMh9n.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/yMh9n.png" alt="Screenshot"></a></p>
  
  <p>I am using MacOS and <code>git version 2.10.1 (Apple Git-78)</code></p>