Enhanced Document support

Null check
Move DisplayText.cs to CSLA
Enhanced Documents – don’t allow ‘Save’ RO on enhanced step
Enhanced Documents windowing
Enhanced Documents remove unnecessary options
Enhanced Documents – don’t allow ‘Save’ transition on enhanced step
Enhanced Documents/Insert,Delete,Paste

PROMS/Volian.Controls.Library/DisplayTabItem.cs

@@ -66,6 +66,12 @@ namespace Volian.Controls.Library
 			get { return _MyUserRole; }
 			set { _MyUserRole = value; }
 		}
+		private bool _Closed = false;
+		public bool Closed
+		{
+			get { return _Closed; }
+			set { _Closed = value; }
+		}
 		/// <summary>
 		/// Current SelectedItemInfo for this page
 		/// </summary>