dbus: Add UUID property to Device1
dbus: Add UUID property to Device1

Adds the initial skeleton to expose UUID property of KNoT devices. Signal
reporting the UUID of a registered device is not implemented yet.

CESARBR/knot-service-source,CESARBR/knot-service-source,CESARBR/knot-service-source,CESARBR/knot-service-source,CESARBR/knot-service-source