Merge pull request #374 from loganfranken/fix/338/doc

Added documentation for Entity/Nav/Breadcrumb #338
Implemented the core adapter for Entity/Nav/Breadcrumb #338
Merge pull request #376 from loganfranken/fix/338/core-adapter

Implemented the core adapter for Entity/Nav/Breadcrumb #338
Added documentation for the Entity/Nav/Breadcrumb SASS variables #338