Update HeroService#create documentation angular#2231

- add short blurb explaining HeroService#create
- include HeroService#create snippet

Author: bignimbus

public/docs/ts/latest/tutorial/toh-pt6.jade

@@ -294,6 +294,10 @@ block get-heroes-details
   When the given name is non-blank, the handler delegates creation of the
   named hero to the hero service, and then adds the new hero to our !{_array}.
 
+  Finally, we implement the create method in the HeroService class.
+
++makeExcerpt('app/hero.service.ts', 'create')
+
   Go ahead, refresh the browser and create some new heroes!
 
 .l-main-section