Add network traffic counters

Signed-off-by: Martin Abente Lahaye <tch@sugarlabs.org>
Update packaging file

Add new sql migration files and update changes log.

Signed-off-by: Martin Abente Lahaye <tch@sugarlabs.org>
Release 0.4.0-1

Signed-off-by: Martin Abente Lahaye <tch@sugarlabs.org>