Add ember data types to blueprint.

Author: chriskrycho

blueprints/ember-cli-typescript/index.js

@@ -62,6 +62,7 @@ module.exports = {
     return this.addPackagesToProject([
       { name: 'typescript', target: 'latest' },
       { name: '@types/ember', target: 'latest' },
+      { name: '@types/ember-data', target: 'latest' },
       { name: '@types/rsvp', target: 'latest' },
       { name: '@types/ember-testing-helpers', target: 'latest' },
     ]);