title: Casing of ./types does not match the underlying filesystem
body: <p>So i had a bit weird warning from eslint</p>
  <p><a href="https://i.stack.imgur.com/lFbta.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/lFbta.png" alt="warning on vscode hints" /></a>
  <a href="https://i.stack.imgur.com/IX1uU.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/IX1uU.png" alt="warning on vscode terminal" /></a></p>
  <p>'./types' is a flow type file.
  I think eslint read checkbox as a lowercase while in reality it is Checkbox (capital C).</p>
  <p>I try <code>git mv casesensitive tmp &amp;&amp; git mv tmp CaseSensitive</code> as discussed here: <a href="https://stackoverflow.com/questions/11183788/in-a-git-repository-how-to-properly-rename-a-directory">In a Git repository, how to properly rename a directory?</a> but it still doesnt work.
  because in the past that folder is lowercase (checkbox) and renamed to Uppercase (Checkbox) but it was work of other developer, i don't know what happen in his machine until this warning come in my machine. Maybe (another assumption) it was happen because of bad config of webpack/babel, im not sure.</p>