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").

- Implemented: FS#3110 - Turn monitoring module into cron jobs

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

Fixed/Implemented: replaced intval() by $app->functions->intval() in all interface functions due to big number problem in intval()

- Bugfix: changed "Return-Path: $form" to Return-Path: $from.

- Fixed UTF-8 support in email function.

Added global functions library which conatins a mail functin that supports attachments and a array_merge function that merges arrays that conatain numeric keys and strings correctly.