Ad serving optimizations

Today I've done some changes to speed up the ad-serving so pages will load faster.

For all eFree-sites ads are now served with a maximum of 1-2 calls instead of up to 3-4 calls.

And for FreeShoutbox.net all ads are now loaded inside an iframe so the page and the ads will load asynchronously for maximum speed.

I might have some more optimizations coming later but this will hopefully speed up things a lot.