* ipv6to4: Ensure interface is brought up automatically on boot.
* Enabling unattended upgrades now ensures that cron is installed and
running to perform them.
* Properties can be scheduled to only be checked after a given time period.
* Fix bootstrapping of dependencies.
* Fix compilation on Debian stable.
* Include security updates in sources.list for stable and testing.
* Use ssh connection caching, especially when bootstrapping.
* Properties now run in a Propellor monad, which provides access to
attributes of the host.
# imported from the archive
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