Higher-level D-Bus stuff

[David Zeuthen <zeuthen gmail com>]

Hey,

So GDBus stuff added in 2.26 didn't really include everything I wanted
to do or that eggdbus did back then. Since then, I've been working on
a) a code/doc-generation tool; and b) abstractions to efficiently work
with many objects with many properties.

Most of this work has been going in my gdbus-binding-tool project at
fdo as well on the dbus list for the
org.freedesktop.DBus.ObjectManager D-Bus interface. I always had
planned for this to be merged into GLib and I've now done that in bug
647577 - please follow up there with comments.

Thanks,
David