Fixed checkoff logic so that it handles Signoff style of checkoffs

The checkoff/signoff list was not always refreshing in the step properties panel.
Added format flag CheckoffOnSubStepsOnly for Bryon and Braidwood

PROMS/VEPROMS User Interface/frmVEPROMS.cs

@@ -1909,6 +1909,7 @@ namespace VEPROMS
 				infotabFoldoutMaint.Visible = infotabRO.Visible = infotabTransition.Visible = infotabTags.Visible = infotabHistory.Visible = infotabApplicability.Visible = false;
 				// When infotabTags is set to InVisible, the matching panel also needs to be set to invisible
 				infotabControlPanelTags.Visible = false;
+				displayTags.MyEditItem = null;
 				displayTags.Visible = false;
 				SelectedStepTabPanel = null;
 				lblItemID.Text = "No Item Selected";