- hooked ssl and ssl_letsencrypt checkboxes

- added limit for letsencrypt and directive snippets selector to client limits
- hide ssl tab if letsencrypt is selected

Conflicts:
	interface/lib/classes/remoting.inc.php
	interface/web/mail/templates/mail_user_backup_list.htm
	interface/web/sites/lib/lang/en_web_backup_list.lng
	interface/web/sites/lib/lang/es_web_backup_list.lng
	interface/web/sites/lib/lang/tr_web_backup_list.lng
	server/plugins-available/backup_plugin.inc.php

    - make sure umlautdomains can be found in lists.
    - sorting by database name did not work in database quota list.
    - IDN: use standard from 2008 (which also works with "ß").

- backported patches