Refresh the list of reminders

[gmarty]

Make sure the list of reminders is always up to date.

Possible solutions:

• Poll the server
• Web Socket connection
• Web Push

Solutions 2 and 3 are preferred as they're event-based and will feel more instantaneous to the user.

[samgiles]

I've implemented option 1, as it's incredibly simple, in #107.

[julienw]

So should we close this @samgiles ?