fixed core and shared module usage, lazy loading modules

src/app/+item-page/item-page-routing.module.ts

@@ -0,0 +1,17 @@
+import { NgModule } from '@angular/core';
+import { RouterModule } from '@angular/router';
+
+import { ItemPageComponent } from './simple/item-page.component';
+import { FullItemPageComponent } from './full/full-item-page.component';
+
+@NgModule({
+  imports: [
+    RouterModule.forChild([
+      { path: ':id', component: ItemPageComponent, pathMatch: 'full' },
+      { path: ':id/full', component: FullItemPageComponent }
+    ])
+  ]
+})
+export class ItemPageRoutingModule {
+
+}