Prepares Ember CLI for new version of ember-welcome-page

- Update ember-welcome-page dependency
-  Re-introduce application.hbs template to include the new
welcome-page component

blueprints/app/files/app/templates/application.hbs

@@ -0,0 +1,5 @@
+{{!-- The following component displays Ember's default welcome message. --}}
+{{welcome-page}}
+{{!-- Feel free to remove this! --}}
+
+{{outlet}}

blueprints/app/files/package.json

@@ -34,7 +34,7 @@
     "ember-export-application-global": "^1.0.5",
     "ember-load-initializers": "^0.5.1",
     "ember-resolver": "^2.0.3",
-    "ember-welcome-page": "^1.0.3",
+    "ember-welcome-page": "^2.0.1",
     "loader.js": "^4.0.10"
   },
   "engines": {

tests/acceptance/smoke-test-slow.js

@@ -183,7 +183,7 @@ describe('Acceptance: smoke-test', function() {
         var dirPath = path.join('.', 'dist');
         var paths = walkSync(dirPath);
 
-        expect(paths).to.have.length.below(23, 'expected fewer than 23 files in dist, found ' + paths.length);
+        expect(paths).to.have.length.below(24, 'expected fewer than 24 files in dist, found ' + paths.length);
       });
   });