Add todoapp benchmark

bench/implementations/ember-2.6.3/app/services/repo.js

@@ -0,0 +1,19 @@
+import Ember from 'ember';
+
+export default Ember.Service.extend({
+	lastId: 0,
+	data: null,
+	findAll() {
+		return this.get('data') || this.set('data', []);
+	},
+
+	add(attrs) {
+		let todo = Object.assign({ id: this.incrementProperty('lastId') }, attrs);
+		this.get('data').pushObject(todo);
+		return todo;
+	},
+
+	delete(todo) {
+		this.get('data').removeObject(todo);
+	}
+});