All announce.d scripts have been moved to /lib/gluon/announce/announce.d
The script /lib/gluon/announce/announce.lua will collect all information
and output json.

This also fixes the type of a few fields which were strings instead of numbers.

For security reasons we should not accept incoming packets per default
and instead allow specific services on specific interfaces.

gluon-mesh-batman-adv should not be used without firewall to prevent forwarding
of packets from the mesh to the wan interface.

For some reason, the firewall package won't work at all without
kmod-ipt-nathelper.

Disabling forwarding prevents the node from reacting to the Subnet-Router
anycast address.