Remove per user DROP, use global DROP instead

Packets that do not find a matching rule will reach the end of the ruleset,
and get dropped by the global DROP rule.
Fix init script
Resolve FQDNs in the recipe

I've had issues where performing the DNS resolution when loading the rules
was slow. Plus, some DNS records will return multiple IP addresses, and we
want to add all of them to the firewall (not just one of them).
For these reasons, AFW will perform a full DNS resolution in the recipe, and
the ruleset will only contain IP addresses.
README cleanup
Merge branch '0.0.6'

Signed-off-by: Julien Vehent <julienv@aweber.com>