Added Foreign Policy support + .tyzden PIano videos

Hey, I've added support for posts and articles at [Foreign Policy](http://foreignpolicy.com) and videos on .tyzden under Piano. I've had it for some time so it is tested, I cannot really find a .tyzden piano video now, but they had them and it worked, FP article e.g. [here](http://www.foreignpolicy.com/articles/2014/08/30/preparing_for_war_with_ukraine_s_fascist_defenders_of_freedom). It is all just quick hacks based on latest fork from here so you might wanna merge it, or do whatever you want ;)