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.

- Improved getSearchSQL() function so that users can use their native date format so search for dates in lists.

 - javascript hooks prepared (onAfterContentLoad is first available hook)
 - new abstract class for GET and POST requests
 - new js.d directory that is included into main template

Added: Changed idn function to support multi-line fields (like mail forward)

- need to have the pecl idn and intl modules installed
  or
- have the idna_convert class in the classes/idn/ path