ece-install :: add munin graphs for TCP connections

[skybert]

It would be nice if ece-install made graphs for e.g. fw_conntrack. This requires autoloading the ip_conntrack module, perhaps by adding it to /etc/modules (for debian at least) or by adding a small script to rc.local... When the module is loaded, munin-node-configure will autosuggest some nice graphs showing the statistics of how many connections are in time_wait, established, etc.