Ask to resend confirmation e-mail

[JeronimoMendes]

Is your feature request related to a problem? Please describe.
Users that don't confirm their e-mail immediately after registration have no way of confirming their e-mail later.

Describe the solution you'd like
Notify user in case he is trying to login without first confirming his e-mail, send a new e-mail and then prompt them to insert the confirmation code

Additional context
Add any other context or screenshots about the feature request here.