HTML Data addition to WET 4.0

As per https://github.com/wet-boew/wet-boew/wiki/GC-Semantic-Web-Implementation-Guide the following has been marked up.

* breadcrumb
* mainContentOfPage
* name
* SiteNavigationElement
* dateModified
Merge pull request #3133 from chrismajewski/v4.0

HTML Data addition to WET 4.0