Avoid patching Devise controllers

[zedtux]

I'm using this gem with the devise_fido_usf gem in order to allow my user to chose a different 2FA option.

The expected workflow would be:

1. Is Google Authenticator enabled? => No
2. Is Fido U2F enabled? => No
3. Redirect to the page to select the option

Then

1. Is Google Authenticator enabled? => Yes
2. Redirect to the check GA page

But as this gem is patching the Devise::SessionsController create action it is not possible to do it.

This gem should use the Warden::Manager.after_authentication callback in order to execute its code instead which would allow the above described workflow.