feat(demo): add landing page with docs (#1951)

docs/app/@core/data/service/descriptions.service.ts

@@ -0,0 +1,41 @@
+import { Injectable } from '@angular/core';
+import { of as observableOf,  Observable } from 'rxjs';
+
+export class Descriptions {
+  icon: string;
+  title: string;
+  description: string;
+}
+
+@Injectable()
+export class DescriptionsService {
+
+  /* tslint:disable:max-line-length */
+  private descriptions: Descriptions[] = [
+    {
+      icon: 'layout-outline',
+      title: 'Efficient',
+      description: 'Packed with a huge number of handcrafted UI components, charts, maps, editors, tables, and much more, so that developers can focus on business needs',
+    },
+    {
+      icon: 'smartphone-outline',
+      title: 'Mobile first',
+      description: 'Looks stunning on every screen size and is optimized to bring the large-screen experience from desktop to mobile',
+    },
+    {
+      icon: 'color-palette-outline',
+      title: 'Сustomizable',
+      description: 'With 3 themes, 2 dashboards, and outstanding UI architecture, it’s easy to change the themes and find the right fit for your company',
+    },
+    {
+      icon: 'heart-outline',
+      title: 'Updated and supported',
+      description: 'Continuous updates and fixes from the development team to keep your tech up to date. The friendly and active community support team are ready to guide you through your challenges',
+    },
+  ];
+  /* tslint:enable:max-line-length */
+
+  getDescriptions(): Observable<Descriptions[]> {
+    return observableOf(this.descriptions);
+  }
+}