Fixed problem with tty

I get the problem below, this commit fix the issue.

```sh
==> default: stdin: is not a tty
==> default:  * Restarting nginx nginx
==> default:    ...done.
==> default: php5-fpm stop/waiting
==> default: php5-fpm start/running, process 2026
==> default: Running provisioner: shell...
    default: Running: inline script
==> default: stdin: is not a tty
==> default:  * Restarting nginx nginx
==> default:    ...done.
==> default: php5-fpm stop/waiting
==> default: php5-fpm start/running, process 2081
==> default: Running provisioner: shell...
    default: Running: inline script
==> default: stdin: is not a tty
==> default: php5-fpm stop/waiting
==> default: php5-fpm start/running, process 2114
==> default: Running provisioner: shell...
    default: Running: inline script
==> default: stdin: is not a tty
==> default: php5-fpm stop/waiting
==> default: php5-fpm start/running, process 2147
==> default: Running provisioner: shell...
    default: Running: inline script
==> default: stdin: is not a tty
==> default: php5-fpm stop/waiting
==> default: php5-fpm start/running, process 2184
==> default: Running provisioner: shell...
    default: Running: inline script
==> default: stdin: is not a tty
==> default: php5-fpm stop/waiting
==> default: php5-fpm start/running, process 2217
```