Updated the Debian installation instructions.

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- Updated ToDo list.

Updated ToDo item list.

Moved server modules and plugins to new directory and updated the installer to create the symlinks for the modules and plugins from *-available to *-enabled directory.
Fixed a typo in mailfilter template.

Added a server module for clients and a mail plugin.

* Cleanup some stuff into login/index.php like globals
* Add errors to the lang files

- Updated todo text

- added a daily cronjob for stats creation in the installer.
- Fixed a bug in the spamfilter white / blacklist forms (thanks to satommy for reporting this)
- fixed ssl cert path in vhost templates/web_domain_ssl.htm
- fixed a bug in the apache plugin which prevented the copying of the standard error and index files.

- enhanced the documentation

Updated apache ssl cert creation.

2.) Cleaned up update.php
3.) Changed definitions for quarantine settings
4.) Commented out areas for quarantining 'clean' and 'other' 

2.) included missing configurations in config.inc.php.master
3.) disabled header & ini_set for shell actions in config.inc.php.master