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

docs/app/@core/core.module.ts

@@ -0,0 +1,40 @@
+/**
+ * @license
+ * Copyright Akveo. All Rights Reserved.
+ * Licensed under the MIT License. See License.txt in the project root for license information.
+ */
+
+import { ModuleWithProviders, NgModule, Optional, SkipSelf } from '@angular/core';
+import { CommonModule } from '@angular/common';
+
+import { throwIfAlreadyLoaded } from './module-import-guard';
+import { DataModule } from './data/data.module';
+
+const PIPES = [
+];
+
+const NB_CORE_PROVIDERS = [
+  ...DataModule.forRoot().providers,
+];
+
+@NgModule({
+  imports: [
+    CommonModule,
+  ],
+  exports: [...PIPES],
+  declarations: [...PIPES],
+})
+export class CoreModule {
+  constructor(@Optional() @SkipSelf() parentModule: CoreModule) {
+    throwIfAlreadyLoaded(parentModule, 'CoreModule');
+  }
+
+  static forRoot(): ModuleWithProviders {
+    return <ModuleWithProviders>{
+      ngModule: CoreModule,
+      providers: [
+        ...NB_CORE_PROVIDERS,
+      ],
+    };
+  }
+}