Implement org.freedesktop.DBus.Properties for exported objects

[gburt]

Exported objects' properties are not accessible via the standard org.freedesktop.DBus.Properties interface.

I'm attaching a first, rough patch for fixing this. It implements Get and Set but not GetAll. It could use some work in terms of checking the requested property interface, etc.

Patch against ndesk-dbus: https://bugs.launchpad.net/ndesk-dbus/+bug/494823/+attachment/1065839/+files/0001-First-rough-pass-implementing-Properties-iface.patch

[bnbot]

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/lifecycle stale