title: How can I test an input type="file" with Browserstack
body: <p>So, I've been trying to test an input type="file" with Browserstack and Intern.js, but I keep getting a "File not found" error because Browserstack searches for the file in my computer. </p>
  
  <p>I know that Browserstack has Upload/Download capabilities, but from their documentation I didn't quite get how to use it.</p>