fixes #6764

- Move translations more to the frontend code

Amavisd supports wildcards by performing decreasingly specific SQL
lookups:
    9 - lookup for user+foo@sub.example.com
    8 - lookup for user@sub.example.com
    7 - lookup for user+foo
    6 - lookup for user
    5 - lookup for @sub.example.com
    3 - lookup for @.sub.example.com
    2 - lookup for @.example.com
    1 - lookup for @.com
    0 - lookup for @.       (catchall)
    (https://www.ijs.si/software/amavisd/README.lookups.txt)

However idn_to_* returns an empty string if the domain has a leading dot
which means lookups 0-3 cannot be used.  This is fixed by removing the
leading dot before encoding or decoding and adding it back just before
returning the domain.

Update interface/lib/classes/remote.d/client.inc.php, interface/lib/classes/functions.inc.php, interface/web/client/client_edit.php files

#4961 modified remote API client edit to include lock and cancel, functions moved from client_edit to functions

- Fixed #4893 Stored XSS issue in email name field

Improved the code that generates the ssh keys for clients and shell users and reorganized it into a central function.

    - 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").

add database-size monitoring. the results stored in the database may be used to add the db-size to the web-quota, too.