C# Класс Rebel.Cms.Web.IO.DocumentTypeIconFileResolver

This will lookup all icon files and then search for any files with an associated CSS file which is named with the same name as the icon. This indicates that the the image file is a sprite file and the CSS file defines the sprites. If this is found, we will remove the sprite icon file from the list, then parse it's sprite names from the CSS file and add their names to the collection.