Add items controller

@joneslee85 

I don't 100% understand the syntax in these tests I wrote. 

Particularly - I can't see where i am using Capybara?

Next Tuesday is DevHub, so I could maybe ask Dan or Geoff if they could give me some tutoring on this?

```
before { get :index }

it "respond... " do
  expect(response)...
end
```