Issue 167 + More

New page transitions HTML structure.

Fixes all mention here https://github.com/h5bp/Effeckt.css/issues/167, here https://github.com/h5bp/Effeckt.css/issues/159, here https://github.com/h5bp/Effeckt.css/issues/98 and here https://github.com/h5bp/Effeckt.css/issues/170.

A couple of improvement, bug fixes and adaptation to the new pages structure.