set 'daemon on;' by default

The default of `daemon off;` is causing salt-minion to hang when executing the nginx service state (i.e. when calling /etc/init.d/nginx start) on Ubuntu 14.04 and 12.04.

Why should this be the default? The nginx docs state that `daemon off;`, while safe to run in production, was originally meant for nginx development purposes: http://nginx.org/en/docs/faq/daemon_master_process_off.html