update FSF address in license text

http://www.gnu.org/licenses/gpl-2.0.html
http://www.fsf.org/about/contact/

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
iptables: missing bracket in iptables-save(8)

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>