feat(new account confirmation e-mail) - send a confirmation email on new account created

- improve reset password to send a link where password can be changed instead of token

[TODO]
Improve the wording of the email
it would be better for the client to define it like `'is_active': {'type': 'bool'}` so we don't duplicate the logic on both sides and we could redefine what active means just on backend. same for needs_activation