changed: there is one dir called root (has parent_id -1)

(we have an owner, group, privileges etc of the root dir)
         the root.id of course is not -1 


git-svn-id: svn://ttmath.org/publicrep/cmslu/trunk@468 e52654a7-88a9-db11-a3e9-0013d4bc506e

core/dircontainer.h

@@ -32,6 +32,8 @@ public:
 
 	DirContainer();
 
+	Iterator GetRoot();
+
 	Iterator Begin();
 	Iterator End();
 	SizeType Size();
@@ -57,6 +59,12 @@ private:
 	// main table with dirs
 	Table table;
 
+	// true if there is a root dir in the table
+	bool is_root;
+
+	// root dir
+	SizeType root_index;
+
 	// indexes
 	TableId table_id;
 	TableParent table_parent;