fix #28 a Constuctor of ColumnDefinition didn't initialize _changed attribute (which was the most likely non-false value)
fix #28 a Constuctor of ColumnDefinition didn't initialize _changed attribute (which was the most likely non-false value)

ridoo/IlwisCore,ridoo/IlwisCore,ridoo/IlwisCore,ridoo/IlwisCore,ridoo/IlwisCore