Monitor Module now has system state

It is now possible to add "navigation-text" without links (actions) to the left navigations-side of the template (needed by the monitor module to add the server-dropdown)

Added new table monitor_data for the core-module monitor.

- updated the debian installation instructions

- added server module for firewall and database.

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.