Assemble: Use nested layouts to dry out markup

Initial work on creating reusable layout inheritance
I understand the urge/instinct to start with a News typeof= for a news article but keeping the webPage object offers a layer of consistency in metadata, eases migration from DC and should help create understandable policy.

The mindset is that if it's HTML it's a webpage, <body> is the backwards compatible shell that will have mandatory properties.  Within that shell you best describe the content with Schema.org fed RDFa Lite 1.1+.

In that you get all the all the flexibility you need to do something as simple as a Contact Us page to the forever reloading meta pinboard style page as Pinterest.

As is works.