[packagekit] New DBus API in master for ::Details

[Richard Hughes]

::Details now has a 'a{sv}' signature in master, rather than the
semi-insane 'ssusst' signature. Giovanni has also added the summary to
the details struct, and in the future we can add other parameters (and
fix things like the installed/available sizes bug) without breaking
API.

PackageKit-qt needs updating, but packagekit-glib should work now, and
also Giovanni has updated the backends to at least compile. Certainly
adding the summary to the backend method in your backend would be very
appreciated. Thanks.

If this works well, we can do the same to UpdateDetails (or rather
merge that into Details??) and make things a lot less complex.

Richard