Add new blog post route

`ember g route posts/new`

We only change enough code to get to the next error message. Getting past the "no route" error only requires creating the route in the routes file.

Red: Element not found when calling `fillIn('.js-post-form-title')`

The next error is simple: no title form field is found to fill text into.

app/router.js

@@ -7,6 +7,9 @@ const Router = EmberRouter.extend({
 });
 
 Router.map(function() {
+  this.route('posts', function() {
+    this.route('new');
+  });
 });
 
 export default Router;

app/routes/posts/new.js

@@ -0,0 +1,4 @@
+import Route from '@ember/routing/route';
+
+export default Route.extend({
+});

app/templates/posts/new.hbs

@@ -0,0 +1 @@
+{{outlet}}

tests/unit/routes/posts/new-test.js

@@ -0,0 +1,11 @@
+import { moduleFor, test } from 'ember-qunit';
+
+moduleFor('route:posts/new', 'Unit | Route | posts/new', {
+  // Specify the other units that are required for this test.
+  // needs: ['controller:foo']
+});
+
+test('it exists', function(assert) {
+  let route = this.subject();
+  assert.ok(route);
+});