[ADF-1881] Consolidate NodeService and NodesApiService (#5591)

* [ADF-1881] Consolidate NodeService and NodesApiService

* * docs added

lib/core/form/models/node-metadata.model.ts

@@ -1,26 +0,0 @@
-/*!
- * @license
- * Copyright 2019 Alfresco Software, Ltd.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-export class NodeMetadata {
-    metadata: any;
-    nodeType: string;
-
-    constructor(metadata: any, nodeType: string) {
-        this.metadata = metadata;
-        this.nodeType = nodeType;
-    }
-}