keep username in sync with primary email
The username = the email is still the first used, even if you change your email.
Here what I've done :
- create an account with sletort@irisa.fr, validate the email
- add the email sebastien.letort@inria.fr, validate the email
- make the 2d email the primary
- remove the email sletort@irisa.fr
- log out
- try to reconnect with my email sebastien.letort@inria.fr <= did not work.
It may be the corretc behaviour, but as a user I was confused and did realise the cause only by looking in the db.
May be a warning should be shown to the user about that.