Point default feeds to marcet.info's mirrors

Signed-off-by: Javier Marcet <javier@marcet.info>
Widen the official regulatory specs

Signed-off-by: Javier Marcet <javier@marcet.info>
dropbear: listen only on ipv4 addresses

Signed-off-by: Javier Marcet <javier@marcet.info>
dnsmasq: upgrade to v2.69 with DNSSEC support

Signed-off-by: Javier Marcet <javier@marcet.info>