[add] a section on multi-user backend

Author: mafanya23

docs/integration/suite_and_backend.md

@@ -14,6 +14,8 @@ The DHTMLX library includes the [DataCollection](/data_collection/) helper that
 
 Thus, to transfer data from your backend to the Suite components, all you need to do is create a valid JSON dataset. You can load it into the component using the [load()](/data_collection/api/datacollection_load_method/) method of DataCollection.
 
+Besides, the DHTMLX library allows providing a [multi-user backend](#multi-user-backend-for-suite-widgets) for any Suite component.   
+
 ## Examples of using DHTMLX Suite widgets with Node.js
 
 Let's have an overview of the examples.
@@ -128,6 +130,12 @@ This example of Grid is visually the same as the previous one but the ways of ad
 
 The following request methods are used in this example: `GET`, `PUT`, `POST`, `DELETE`.
 
+## Multi-user backend for Suite widgets
+
+You can create a multi-user (real-time updated) backend for Suite widgets. The backend can be implemented in any language and you can use any library to allow the client and the server sides interact via the WebSocket protocol.
+
+There is an [example](https://github.com/DHTMLX/nodejs-suite-demo/blob/master/public/views/12_grid_with_form_multiuser.html) that shows a multi-user backend for Grid, implemented with the help of Node.js and the Faye library. You can provide live data updates for any Suite widget based on this example.
+
 :::info
 Download and take a look at the [Examples of using DHTMLX Suite widgets with Node.js](https://github.com/DHTMLX/nodejs-suite-demo).
-:::
+:::

docs/whatsnew.md

@@ -22,19 +22,13 @@ This version brings some updates in the API methods. Check the [Migration](migra
 
 #### Common features
 
-- Multi-user (live update) backend for Suite widgets
+- [Multi-user (live update) backend](integration/suite_and_backend.md#multi-user-backend-for-suite-widgets) for Suite widgets
 
 #### Grid 
 
 - [Row expander](grid/configuration.md#row-expander) with the possibility to insert any Suite widget or HTML content (PRO version)
 - [Multi-sorting](grid/usage.md#sorting-by-multiple-columns) functionality that allows sorting Grid by several columns (PRO version)
 
-### Updates
-
-#### Grid
-
-- Improved and extended export to Excel functionality 
-
 ### Fixes
 
 - DataCollection. The `sort()` method called without arguments doesn't reset the applied sorting