+ Added TreeNode.RemoveChild
+ Added Directory.Copy
+ Path.Combine now replaces alt directory separator
+ Project: Renamed ProjectName to Name
+ Project.Load: Save settings, if file doesn't exist
+ AssetHierarchy: Exposed RootNode
+ ContentBrowserWindow: Fixed Empty Folder not being Leaf-Node
+ TreeNode: Added IsParentOf, IsChildOf and IsInSubtree.
+ Fixed InternalDeleteTreeAndChildren for null trees