Improve the cookie name regexp
The current regexp is qr/^[a-zA-Z]\w*$/.
It has several drawbacks :
- \w is locale dependent (and accept accents in some languages)
- Doesn't accept dash (-)
Proposed regexp: qr/^[a-zA-Z][a-zA-Z0-9_-]*$/.
NB: In lemonldap-ng-manager/lib/Lemonldap/NG/Manager/_Struct.pm, line 1775.