cloudstack-packages: fixes install_packages (diff -> diffutils),
use debconf-set-selections for iptables-persistent
preseed.cfg : change root password, use separate partitions for /usr /var /home
definition.rb: reset timeout to sane value
cleanup.sh, zerodisk.sh: move wipe of root directory to zerodisk
CLOUDSTACK-1066: no need for busybox and dictionaries
CLOUDSTACK-1066: fix bug in generating signature
CLOUDSTACK-1066: don't confuse veewee about root password
Clean up stuff copied in to vm by veewee