Demo links in README no longer working

[MikkelvtK]

Hi,

I was browsing through Elixir repo's and stumbled on your interesting project! When reading the README I noticed the following.

Environment

• Operating system: Windows 10
• Web browser: Firefox

Current behavior

The demo section in the README has a few links that are no longer working.

Section I'm referring to:

Response I'm getting:

Expected behavior

Seeing the demo when opening the link.