EDMI: Add 3-tier database access in DatabaseWithFallback, add client config,

EDMI Service: Version 2.4.0.0
EDMI: API: Version 1.4.0.0

Service.EDMIService/Methods/IDB/AttributeValue.vb

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+Namespace Methods.IDB
+
+    Public MustInherit Class BaseAttributeValue
+
+    End Class
+
+    ''' <summary>
+    ''' Attribute values supplied by the user
+    ''' </summary>
+    Public Class UserAttributeValue
+        Public Property Id As Integer
+        Public Property Name As String
+        Public Property Values As List(Of String)
+        Public Property ControlName As String
+
+        Public Overrides Function ToString() As String
+            Return Name
+        End Function
+
+        Public Overrides Function GetHashCode() As Integer
+            Return Name.GetHashCode()
+        End Function
+    End Class
+
+    Public Class AutoAttributeValue
+        Inherits BaseAttributeValue
+    End Class
+
+    Public Class SystemAttributeValue
+        Inherits BaseAttributeValue
+    End Class
+
+End Namespace