Set the avahi hostname when making an image

src/freedombone-image-customise

 chroot "$rootdir" apt-get install -y iptables dnsutils net-tools network-manager iputils-ping
 chroot "$rootdir" apt-get install -y libnss-mdns libnss-myhostname libnss-gw-name nano man ntp
 
+sed -i "s|#host-name=.*|host-name=${PROJECT_NAME}|g" $rootdir/etc/avahi/avahi-daemon.conf
+
 chroot "$rootdir" /bin/bash -x <<EOF
 git clone https://github.com/bashrc/freedombone /root/freedombone
 cd /root/freedombone