docs: added links to demos

Author: hakimio

docs/SUMMARY.md

@@ -3,6 +3,7 @@
 - Getting Started
   - [Introduction](introduction/intro.md)
   - [Migration Guide](introduction/migration-v19.md)
+  - [Demos](introduction/demos.md)
 - CDK
   - [@angular-ru/cdk/typings](cdk/typings.md)
   - [@angular-ru/cdk/number](cdk/number.md)

docs/cdk/logger.md

@@ -48,7 +48,7 @@ export const appConfig: ApplicationConfig = {
 };
 ```
 
-[**Online demo**](https://angular-ru.github.io/angular-ru-logger-example-app)
+[**Online demo**](https://angular-ru.github.io/angular-ru-sdk/logger-demo)
 
 ![](https://habrastorage.org/webt/lq/a9/_s/lqa9_sp8gxkwax_sy6x9w3qf5ry.gif)
 

docs/cdk/tooltip.md

@@ -2,7 +2,7 @@
 
 ## Introduction
 
-[**Demo**](https://angular-ru.github.io/angular-ru-tooltip-example-app)
+[**Demo**](https://angular-ru.github.io/angular-ru-sdk/tooltip-demo)
 
 ```bash
 $ npm install @angular-ru/cdk/tooltip

docs/cdk/virtual-table.md

@@ -3,7 +3,7 @@
 The Angular Table Builder includes a comprehensive set of ready-to-use features covering everything from paging,
 sorting, filtering, editing, and grouping to row and column virtualization, and accessibility support.
 
-[**Demo**](https://angular-ru.github.io/angular-ru-ng-table-builder-example-app)
+[**Demo**](https://angular-ru.github.io/angular-ru-sdk/virtual-table-demo)
 
 ```bash
 $ npm install --save @angular-ru/cdk

docs/introduction/demos.md

@@ -0,0 +1,12 @@
+## Demos
+
+The following demos are available:
+
+- [CDK Demo](https://angular-ru.github.io/angular-ru-sdk/)
+- [Excel Demo](https://angular-ru.github.io/angular-ru-sdk/excel-demo/)
+- [Flex Layout Demo](https://angular-ru.github.io/angular-ru-sdk/flex-layout-demo/)
+- [Http Demo](https://angular-ru.github.io/angular-ru-sdk/http-demo/)
+- [Logger Demo](https://angular-ru.github.io/angular-ru-sdk/logger-demo/)
+- [NGXS Demo](https://angular-ru.github.io/angular-ru-sdk/ngxs-demo/)
+- [Tooltip Demo](https://angular-ru.github.io/angular-ru-sdk/tooltip-demo/)
+- [Virtual Table Demo](https://angular-ru.github.io/angular-ru-sdk/virtual-table-demo/)