Finalizes LDAP connection of user management
* Add check if username is used in LDAP yet * Create user in LDAP * Change user in LDAP * Password update in LDAP * No password update from TYPO3 backend
* Add check if username is used in LDAP yet * Create user in LDAP * Change user in LDAP * Password update in LDAP * No password update from TYPO3 backend