Moodle authentication method which provides all functionality of auth_ldap, but supports advanced features for the LDAP synchronization script: On the one hand, it adds the possibility to the LDAP synchronization script to suspend users which have disappeared in LDAP for a configurable amount of days and delete them only after this grace period (the Moodle core LDAP synchronization script only provides you the option to suspend _or_ delete users which have disappeared in LDAP). On the other hand, you can prevent the LDAP synchronization script from creating Moodle accounts for all LDAP users if they have never logged into Moodle before (the Moodle core LDAP synchronization script always creates Moodle accounts for all LDAP users).