include: cache copy of nfnetlink_conntrack.h

To ensure that examples compile in any installation. This header
is not installed in the system.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
examples: netfilter: add nfct daemon skeleton code

This patch adds the skeleton code for a daemon that collects statistics
via ctnetlink. Consider it a simplified version of ulogd2. It also
contains some documentation on several interesting tweaks.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
include: don't force compiler to enter C++11 mode

Thomas reports that g++ forces you to enable C++11 mode if
you want to use <cstdint>. Tested with g++ (GCC) 4.4.4. He
reports that this compiles fine without the special headers.
So let's get rid of them. This reverts bb8c40e.

Reported-by: Thomas Jarosch <thomas.jarosch@intra2net.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Tested-by: Thomas Jarosch <thomas.jarosch@intra2net.com>