The Platform Toolkit is a material to guide content sharing platforms when adding the option of CC licensing. These aren't hard-set requirements, but suggestions on how to make the implementation smooth for users and platform alike. The process towards building it was described in a series of blog posts on the CC Open Source blog.
The new toolkit is placed in the platform-toolkit folder along with a frozen copy of the Vocabulary stylesheets ( here's more information about Vocabulary). By opening the index.html file in this folder you should be able to visualize the platform toolkit page. Everything pertaining to the previous toolkit and model platform material is placed in the deprecated folder.
The header is just a placeholder image inside an empty div with the class "mock-header".
Licensed under the Expat/MIT license.