title: Switching between ad networks in cocos2d v3.0 and spritebuilder
body: <p>as the title would suggest i'm trying to make a system that automatically will prioritize my ad networks and display the next in line when one fails to load. I currently have iAd implemented and working following this example: <a href="https://stackoverflow.com/questions/17815777/how-to-add-iad-in-cocos2d/17816415#17816415">How to add iad in cocos2d?</a> and I plan on using the example provided by the same person, Guru, to implement AdMob. Example found here: <a href="https://stackoverflow.com/questions/21846346/admob-with-cocos-2d-v3">AdMob with Cocos2d v3</a>. Now preferably I would like to just add on/change the working code as it is very well built and organized. Along with prioritizing iAd followed by AdMob, I would like to also have revmob as well. I was thinking of just doing revmob as the fullscreen ad when launched, but I would still like to know how I would go about adding the revmob banners to the rotation just as good measure. If any of my code is needed I'll gladly post it :)  </p>