have css classes on document tree to be able to do document type specific icons

[dbu]

there seems to be some configuration for this in the sonata admin bundle but its not used in the tree provider https://github.com/sonata-project/SonataDoctrinePhpcrAdminBundle/blob/master/DependencyInjection/Configuration.php#L76-L79

this will partially be the responsiblity of the ResourceBundle

[wouterj]

This is not yet implemented in FancyTree afaics: mar10/fancytree#406

[wouterj]

It was implemented, we can start working on this as soon as #84 is merged.