Nodes cannot be sorted

There are no properties for sorting items within a tree.

Implemented five sorting modes:

   etvwNoSort = 0
   etvwAlphabetic = 1
   etvwItemDataThenAlphabetic = 2
   etvwTagThenAlphabetic = 3
   etvwCustomSortEvent = 4

No sort is the default. The next three modes are implemented internally within the control, and the last one raises a CustomSort event which allows an arbitrary sort order to be defined.

Sorting can either be configured to occur automatically as child nodes are added using the ChildSortMode property of a node, or can be manually triggered using the Sort method of a node. Note that setting ChildSortMode and then adding a large number of items is *very* slow; it is better to first add all of the items and then use the Sort method.

The Sorted property of a node is still not implemented, this should be deprecated.