IdServer - Implement 'Forgot password' feature

[simpleidserver]

Discussion : #643

Check policy builder in the admin website is working.

Worfklow :

• Send a password reset email.
• If the user receives multiple password reset emails, only the password link in the most recent email is valid.
• URL Lifetime determines how long the link is valid.

OTP code must be sent.

TODO

• In the user screen, explains what is the "Notification Mode" (used during the back channel authentication) : DONE
• Add "console" authentication type : DONE
• Display errors when reset link cannot be send : DONE
• Can hide "reset password" link : DONE