- Revert back to SHA1 as HMAC hash function so that it works with Google authenticator
- Add message to user to tell him to run /2fa confirm to add a TOTP code
- Split TotpService further into GenerateTotpService and TotpAuthenticator, which wraps the GoogleAuthenticator impl
- Add missing tests for the services
- Change GenerateTotpService's interface to behave like a collection for more intuitive method behavior