[2.3] - Fix folder icon on container resources without any children +...

...Prevent icon colors/font-style changes for unpublished resources

To summarize : 

* when a resource marked as "container" had no children, the folder icon wasn't displayed
* when a resource was unpublished, its icon color was "light grey" and in italic (which could led to "dirty" rendering)

On the first point, using `fa-folder-o` (white folder) might be an option to put the focus on the fact the container is empty.

On the last point, i would say icons should not change according to the resource's published status (the node "label" changes being enough to reflect that status).