feature suggestion: wildcard in userdb
aa:x:32009:32012::/home/usr/mail/bb::userdb_quota_rule=*:bytes=700M
*:x:32009:32012::/home/usr/mail/bb:
That would be usefull in many situation, for example to set default
values per domain (userdb per domain)
userdb {
driver = passwd-file
args = /usr/dovecot-cfg/userdb/%d
}