feat: add a bunch of new Nebular demos (#1911)

src/app/pages/bootstrap/bootstrap-routing.module.ts

@@ -0,0 +1,33 @@
+import { NgModule } from '@angular/core';
+import { Routes, RouterModule } from '@angular/router';
+
+import { BootstrapComponent } from './bootstrap.component';
+import { ModalsComponent } from './modals/modals.component';
+import { ButtonsComponent } from './buttons/buttons.component';
+import { FormInputsComponent } from './form-inputs/form-inputs.component';
+
+
+const routes: Routes = [{
+  path: '',
+  component: BootstrapComponent,
+  children: [
+    {
+      path: 'inputs',
+      component: FormInputsComponent,
+    },
+    {
+      path: 'buttons',
+      component: ButtonsComponent,
+    },
+    {
+      path: 'modal',
+      component: ModalsComponent,
+    },
+  ],
+}];
+
+@NgModule({
+  imports: [RouterModule.forChild(routes)],
+  exports: [RouterModule],
+})
+export class BootstrapRoutingModule { }