Synnefo

Improve email/username handling

- New helper methods in AstkosUser.objects
- Check uniquness between username/email on user creation process
- Allow login using both username/email fields
- Keep email case intact
- Store lowercase email in username field

Remember last login method

when multiple login methods are enabled in settings only the primary one
is visible by default in the login page. Keeping last successful login
method in a cookie allows us to override that behaviour and improve user
experience for users that login using secondary login methods.

Force secondary login methods display

in third party account assigment to existing account process

Modal box style fix

Update messages