lxc-clone: Exclude /run during clone

Since wheezy, /var/run is replaced with /run. Since /var/run is now a
symlink, we can just include it in the clone.
modules: Add default configuration
modules: Automatically load ipmi modules
system: Enable getty on the third serial port

This serial port is connected to the IPMI Serial-over-LAN port.
apt: Add deb-src entry for sid to sources.list
apt: Add vuurmuur to sources.list
system: Update various config files after upgrade
lxc: Update the way containers are set to autostart

In older versions, this happened through symlinks in /etc/lxc/auto.
Since 1.0, this happens by setting a value inside the container
configuration.
fail2ban: Block on dovecot connections without auth attempts too

These turned up a lot in the logs lately, so lets just block those
attempts as well after a few times.
fail2ban: Add my IP to the whitelist
rc.local: Add default script
kernel: Disable bridge-nf-call-iptables

This works around a problem in the network setup, as described here:

http://www.stderr.nl/Blog/Software/Linux/BouncingPacketsKernelBug.html
avahi: Only use the br-lxc interface

This prevents broadcasting on the external network, or on the veth
interfaces directly.