feature #5516 :   The access to a file managed by Silverpeas and located in the filesystem is now performed through the SilverpeasFile and SilverpeasFileFactory classes. SilverpeasFile represents now a file in Silverpeas whereas SilverpeasFileFactory wraps the way to access them according to some business rules (attachment, file serving, ...). These new classes are now used by the following servlets: FileServer and any subclasses of AbstractFileSender class