Add indicator for confirm cancel, set after passing key markers

- Issue
MatterHackers/MCCentral#5487
Mechanism required to only show wizard cancel confirmation when appropriate

MatterControlLib/ConfigurationPage/PrintLeveling/SetupWizards/PrinterSetupWizard.cs

@@ -74,6 +74,8 @@ namespace MatterHackers.MatterControl
 
 		public Vector2 WindowSize { get; protected set; }
 
+		public bool RequireCancelConfirmation { get; protected set; }
+
 		public virtual bool ClosePage()
 		{
 			return true;