Support email notification

[McSinyx]

Aight I'm actually not sure if we do notification faster via email or [a dedicated notification page].

Originally posted by @Huy-Ngo in #64 (comment)

[Huy-Ngo]

I was so sure that it's just sending using a short script like in the example but now I just tried and failed making config to send mail :(

[Huy-Ngo]

Previously I just test for sending mail locally so it worked but not now.

[McSinyx]

Well it should work, we can try again later. The advantage of emails is that we don't need to store these info on our DB thanks to email servers and clients.

[Huy-Ngo]

We can ask our profs for how to config since they should probably have already had them in some other server(s).

ETA: This tutorial might help: https://www.digitalocean.com/community/tutorials/how-to-install-and-configure-postfix-as-a-send-only-smtp-server-on-ubuntu-20-04

[Huy-Ngo]

Too bad my summer project was setting up SMTP server to receive email and not sending. 🤦‍♂️