Add basic auth and account activation

[AtrikDas]

No description provided.

[harsh183]

I'll merge this after the email activation stuff is working.

Note that for email to actually work we need to enable some SMTP service or server like Sendgrid.

Also making accounts this way by hand is quite difficult so we shall also set up some seed data to work with as well.

[harsh183]

Looks good now. For actually sending the emails to real email #24 will need a PR as well. I went through all files and it looks fine.