Small code cleanup.

I4AASNodeManager.cs

@@ -202,89 +202,6 @@ private void AddNodesFromNodesetXml(string nodesetFile)
             }
         }
 
-        public static Referable? FindReferableByReference(AssetAdministrationShellEnvironment environment, Reference? reference, int keyIndex = 0)
-        {
-            if (environment == null || reference == null)
-            {
-                return null;
-            }
-
-            var keyList = reference?.Keys;
-            if (keyList == null || keyList.Count == 0 || keyIndex >= keyList.Count)
-            {
-                return null;
-            }
-
-            var firstKeyType = keyList[keyIndex].Type;
-            var firstKeyId = keyList[keyIndex].Value;
-
-            switch (firstKeyType)
-            {
-                case KeyElements.AssetAdministrationShell:
-                {
-                    var aas = environment.AssetAdministrationShells.Where(
-                        shell => shell.IdShort.Equals(firstKeyId,
-                        StringComparison.OrdinalIgnoreCase)).First();
-
-                    if (aas == null || keyIndex >= keyList.Count - 1)
-                    {
-                        return aas;
-                    }
-
-                    return FindReferableByReference(environment, reference, ++keyIndex);
-                }
-
-                case KeyElements.GlobalReference:
-                {
-                    var keyedAas = environment.AssetAdministrationShells.Where(
-                        globalRef => globalRef.AssetInformation.GlobalAssetId.Equals(firstKeyId,
-                        StringComparison.OrdinalIgnoreCase)).First();
-
-                    if (keyedAas != null)
-                    {
-                        return keyedAas;
-                    }
-
-                    return null;
-                }
-
-                case KeyElements.ConceptDescription:
-                {
-                    var keyedAas = environment.ConceptDescriptions.Where(
-                        description => description.IdShort.Equals(firstKeyId,
-                        StringComparison.OrdinalIgnoreCase)).First();
-
-                    if (keyedAas != null)
-                    {
-                        return keyedAas;
-                    }
-
-                    return null;
-                }
-
-                case KeyElements.Submodel:
-                {
-                    var submodel = environment.Submodels.Where(
-                        description => description.IdShort.Equals(firstKeyId,
-                        StringComparison.OrdinalIgnoreCase)).First();
-
-                    if (submodel == null)
-                    {
-                        return null;
-                    }
-
-                    if (keyIndex >= keyList.Count - 1)
-                    {
-                        return submodel;
-                    }
-
-                    return FindReferableByReference(environment, reference, ++keyIndex);
-                }
-            }
-
-            return null;
-        }
-
         public void CreateObjects(AssetAdministrationShellEnvironment env)
         {
             string typeNodeId = "ns=" + Server.NamespaceUris.GetIndex("http://opcfoundation.org/UA/I4AAS/").ToString() + ";i=";