Upgrade ember-cli and ember.js

They fixed the css concat problem in ember-cli 0.0.6. But then I ran into a
problem with jquery.js or something and it disappeared when I went with the
bleeding edge ember.js (1.5.0-beta.4).

The commands to upgrade were something like this:

```bash
npm update -g ember-cli
mv todo todo-previous
mkdir todo
cd todo
ember init
cp -r ../todo-previous/.git .git
git add .
git commit
```

They fixed the css concat problem in ember-cli 0.0.6. But then I ran into a
problem with jquery.js or something and it disappeared when I went with the
bleeding edge ember.js (ember 1.5 beta 4 or something; check bower.json).