Add category_sets to piece
Add mobile preview link to doc detail page
Add mobile preview link to doc detail page
Set state 'hidden' if no calendar/map content selected
Revise marker category order
Remove duplicated order
Now use unique sort key to sort marker by category
Hide initial category_set into piece
Remove unused brackets
Now use unique sort key to sort marker by category

Conflicts:

	app/models/map/content/marker.rb
Sort category_sets
Change attribute name
Hide state selection if no content specified
Move doc partial to shared directory
Now doc image links to doc page
Add category with link to doc style
Add gp_article_content_docs to piece setting
Add docs_order to piece setting
Add doc_style to piece setting
Add new settings to show page