title: How can I get 'ng serve -o' to launch a page other than index.html?
body: <p>Our angular app will be embedded in an iframe when in production. In development, we have a file, host.html, which has an iframe whose src is the angular app's index page. We can 'ng serve' and then manually bring up host.html and it works fine.</p>
  
  <p>But, 'ng serve -o' wants to open up the app index file; how do I make it open host.html instead?</p>