Edit few things.

These are actually equivalent:

```
ubuntu                    latest              99ec81b80c55        11 weeks ago        266 MB
ubuntu                    14.04               99ec81b80c55        11 weeks ago        266 MB
ubuntu                    trusty              99ec81b80c55        11 weeks ago        266 MB
```

 If you dont have trusty in your images list you can even do:

```
docker tag 99ec81b80c55 ubuntu:trusty
```