sort versions and print them as listing

before this patch:

```
$ vagrant box remove --box-version 0.2.9 berendt/ubuntu-14.04-amd64
You requested to remove the box 'berendt/ubuntu-14.04-amd64' version '0.2.9' with
provider 'virtualbox', but that specific version of the box is
not install. Please double-check and try again. The available versions
for this box are:

0.2.11, 0.2.10
```

after this patch:

```
You requested to remove the box 'berendt/ubuntu-14.04-amd64' version '0.2.9' with
provider 'virtualbox', but that specific version of the box is
not install. Please double-check and try again. The available versions
for this box are:

 * 0.2.10
 * 0.2.11
```