Add labs support

Enable labs for all environment at once with a *gorgeous* interactive console.

```bash
> be hanzo install labs

-----> Activating Heroku Labs
       Add preboot? yes
       - Enabled for qa
       - Enabled for staging
       - Enabled for production
       Add user-env-compile? yes
       - Enabled for qa
       - Enabled for staging
       - Enabled for production
```