Merge commit 'refs/merge-requests/337' of git://gitorious.org/noosfero/noosfero into merge-requests/337

Conflicts:
	app/controllers/public/catalog_controller.rb
	app/helpers/application_helper.rb
	app/helpers/catalog_helper.rb
	app/views/catalog/index.rhtml
	public/stylesheets/application.css

Conflicts:
	public/stylesheets/application.css
product-categories-block: not visible when products are disabled on the environment
Use custom design for catalog

This allow the ProductCategories block to be shown only on the catalog
and not on every profile page