Conflict when with a sub database named as account

[camlafit]

Hi

If we have an alternc user toto , by default first database to create will ba toto and its mysql user will be also toto.

If for any reason we want a sub database named also toto , we expect to get an user and database named toto_toto
Actually database toto_toto is created but not the mysql user.

Indeed at https://github.com/AlternC/AlternC/blob/master/bureau/class/m_mysql.php#L661-L664 we force mysql user with its alternc account when sub part as same named.
In this case toto_toto user can't be set.