Simplified "add new screen" process

This pull request is only nonfunctional.

With these changes, adding a new screen is now a simple 2-step process. Simply add an HTML template wherever you want under the templates/ folder, and then add a navbar link in util.js. When the navbar renders, it will automatically generate a link to the screen in the navbar, and the router will automatically load the correct template given the URL if that new menu item is clicked-on. 

I removed all notion of subrouters and controllers, as they are extreme overkill for a mostly-static-pages site.

I think it's time to start adding legitimate content to this site now. I'll open an issue to investigate having a left-side menu, and we can discuss it there.

-John