Check if template is list or string type in config context

[TheNetworkGuy]

As pointed out by @Albert-LGTM in #30, its quite confusing if you use a string instead of a list format structure in the config context. This was originally a string format (since most users only apply one template on a host) but was extended to support multiple.

Its a good idea to implement backwards compatibility so that users can choose between:

• A single template in a string format
• A single template in a list format
• Multiple templates in a list format

[TheNetworkGuy]

Should be live, simple fix.