Initialize Borders from FlexGrid selection

Eliminate SelChange funtions during Initialization
Eliminate Moving GridItem to the Left and Right on selection
Fixed a bug where SelectedEditItem was null
Eliminate SelChange funtions during Initialization
Use FlexGrid CellRange (Selection) to Get and Set Range Borders
Added Unknown value to GridLinePattern enum
Set Range Borders based upon CellRange (Selection)

PROMS/Volian.Controls.Library/VlnBorders.cs

@@ -438,6 +438,7 @@ namespace Volian.Controls.Library
 	}
 	public enum GridLinePattern : int
 	{
+		Unknown = -1,
 		None = 0,
 		Single = 1,
 		Double = 2,