docs(aio): update migrated content from anguar.io

aio/content/examples/attribute-directives/src/app/dummy.module.1.ts

@@ -0,0 +1,17 @@
+// Not used. Keep away from plunker
+// Keeps ATLS from complaining about undeclared directives.
+import { NgModule } from '@angular/core';
+import { BrowserModule } from '@angular/platform-browser';
+
+import { AppComponent }               from './app.component.1';
+import { HighlightDirective as HLD1 } from './highlight.directive.1';
+import { HighlightDirective as HLD2 } from './highlight.directive.2';
+import { HighlightDirective as HLD3 } from './highlight.directive.3';
+
+@NgModule({
+  imports: [ BrowserModule ],
+  declarations: [
+    AppComponent, HLD1, HLD2, HLD3
+  ]
+})
+export class DummyModule { }