Fixed issue JAM-Software#756 (OnMeasureItem called before data is ass…

…igned to node): AddChild() now calls InsertNode()

Update CHANGES.txt

V6.6.0

V6.5

V6.4.1

V6.4

Changes of V6.3

Merge branch 'master' of https://github.com/Virtual-TreeView/Virtual-…

…TreeView

VTVersion = '6.2.1'

Corrected LibSuffix