[ADF-2670] Added new docs for 2.3 features (#3181)

docs/core/comment-content.service.md

@@ -0,0 +1,33 @@
+---
+Added: v2.3.0
+Status: Active
+Last reviewed: 2018-04-12
+---
+
+# Comment Content service
+
+Adds and retrieves comments for nodes in Content Services.
+
+## Class members
+
+### Methods
+
+-   `addNodeComment(nodeId: string, message: string): Observable<CommentModel>`<br/>
+    Adds a comment to a node.
+    -   `nodeId: string` -  ID of the target node
+    -   `message: string` -  Text for the comment
+    -   **Returns** `Observable<CommentModel>` - Details of the comment added
+-   `getNodeComments(nodeId: string): Observable<CommentModel[]>`<br/>
+    Gets all comments that have been added to a node.
+    -   `nodeId: string = null` -  ID of the target node
+    -   **Returns** `Observable<CommentModel[]>` - Details for each comment
+
+## Details
+
+See the Comments API section of the
+[Alfresco JS API docs](https://github.com/Alfresco/alfresco-js-api/blob/master/src/alfresco-core-rest-api/docs/CommentsApi.md#addComment)
+for more information about the underlying REST API.
+
+## See also
+
+-   [Comment process service](comment-process.service.md)