Add additional files to snack bar component example (#73)

* Add additional files to snack bar component example

* Fix lint

Author: tinayuangao

src/app/examples/example-module.ts

@@ -145,7 +145,10 @@ export const EXAMPLE_COMPONENTS = {
   'slide-toggle-overview': {title: 'Basic slide-toggles', component: SlideToggleOverviewExample},
   'snack-bar-component': {
     title: 'Snack-bar with a custom component',
-    component: SnackBarComponentExample
+    component: SnackBarComponentExample,
+    selectorName: 'SnackBarComponentExample, PizzaPartyComponent',
+    additionalFiles:
+      ['snack-bar-component-example-snack.html', 'snack-bar-component-example-snack.css']
   },
   'snack-bar-overview': {title: 'Basic snack-bar', component: SnackBarOverviewExample},
   'tabs-overview': {title: 'Basic tabs', component: TabsOverviewExample},