How to create a splash screen or progress loading bar in Ember web app

As an example:

http://ift.tt/1nF8qfU

If you visit this page, you see first the activity indicator, then the page loads up. It feels like splash screen. The site seems built in Ember.js 1.x. I like the idea to have such splash screen, better than nothing especially when the network speed is slow.

How to implement this feature in Ember? Any good addon?