[Desktop13.04-Topic] Switch to PackageKit 0.8.x

[Matthias Klumpp]

Hi!
There have been many changes on PackageKit recently. The 0.8.x series
broke API, so we are now able to do very clever cache handling in
PackageKit backends, also we changed the DBus interaction to be a lot
faster and did some improvements on the core, which will also result
in increased speed due to less overhead.
The new PackageKit also contains the possibility to run transactions
in parallel, which provides another speed gain. The frontend API has
been simplified, so it is now easier to use and more extendable.
Also PackageKit now contains a few cool new features - like
systemd-interaction. (inhibiting shutdown on upgrade & showing error
messages) Also offline-upgrades are possible, if a recent enough
Plymouth version is present. I don't know if these features are wanted
in Ubuntu, but at least for the huge improvements made in PackageKit
0.8.x I suggest upgrading it to 0.8.x in the next cycle.

Also, it would be very cool if the Aptcc backend of PackageKit (the
current default backend) would receive the same improvements on
Ubuntu-specific stuff like Aptdaemon did, so that most Ubuntu tools
are usable with Aptdaemon and PackageKit.
Most Aptd features are already present in PackageKit for a long time
and just need implementation in the Aptcc backend. (which currently
doesn't cover all features of PackageKit)
The most recent PackageKit, including dependent packages, is available
in Debian Experimental for testing. Aptd would need to be updated,
because it's compatibility-layers will most likely not work with the
changes done in PK.
Kind regards,
   Matthias