Setting up a HTTP web server on AWS needs changes to webserver_example.py

[JAQuent]

I've tried to get the web server working on an AWS EC2 instance and I still got a CORS error in my browser.

It worked when I changed the last line in https://github.com/immersivecognition/unity-experiment-framework/blob/master/webserver_example/webserver_example.py

to app.run(host='0.0.0.0', port=5000, debug=True)