Associate product properties with property categories.
Require assets required for the dummy app and the engine.

Requires sass-rails > 4.0.2

See:
http://stackoverflow.com/questions/22392862/undefined-method-environment-for-nilnilclass-when-importing-bootstrap?answertab=active#tab-top
Allow the creation of property categories through controllers.

This follows the same example as property_name= in the original
controller.

The product properties controller does not manage the creation or
updating of product properties, instead it uses the products controller
and the nested attributes on the product. This allows that behavior for
categories.
Bring in property views from spree.

These will be heavily modified and/or completely rewritten.