basic implementation of ICE failure notifications in chat window
added missing tests for NotificationView
added link to ice candidate state specification
Merge with master
Merge pull request #281 from n1k0/failed-ice-connection-notification

ICE failure notifications in chat window
Server: move the SESSION_SECRET to env vars

This does not fix the fact that the session secret is actually secret at
deployment. For now, in production it will use the session secret available in
.awsbox.json.
Address pull request comments
Merge pull request #294 from tOkeshu/fix-session-secret

Move the SESSION_SECRET to env vars