Qual: Move error string in errors lang file.

htdocs/adherents/fiche.php

htdocs/install/etape5.php

htdocs/langs/en_US/errors.lang

htdocs/langs/en_US/users.lang

htdocs/langs/fr_FR/errors.lang

htdocs/langs/fr_FR/users.lang

htdocs/langs/it_IT/errors.lang

htdocs/langs/it_IT/users.lang

htdocs/langs/pt_PT/errors.lang

htdocs/langs/pt_PT/users.lang

htdocs/user/fiche.php

htdocs/user/group/fiche.php