`deploy_script` now accepts dictionaries for `minion_conf` and `master_config` not strings.

Refs saltstack/salt#5849
Refs saltstack/salt-cloud#672
The `ec2` driver now uses `dict`s for the `{master,minion}_conf` parameters in `saltcloud.utils.deploy_script`. Refs #672
The `cloudstack` driver now uses `dict`s for the `{master,minion}_conf` parameters in `saltcloud.utils.deploy_script`. Refs #672
The `digital_ocean` driver now uses `dict`s for the `{master,minion}_conf` parameters in `saltcloud.utils.deploy_script`. Refs #672