IPSec with DNSSEC v2

Back to our business. On 11 Oct a patch to enable DNSSEC protected DANE CERTs was merged to StrongSWAN's upstream so now you can have interoperability between racoon and strongswan if you need to use CERTs for easy deployment.

The approach is pretty the same, only with StrongSWAN you have additional DNSSEC validation (racoon blindly trusts underlying DNSSEC implementation).