Add templating support with scriban

[JeevanJames]

The scriban template must have access to the variables dictionary. It will need to be resolved before any JSON processing, since the template itself will not be valid JSON.

[JeevanJames]

Scriban support added. The Scriban templates can access the resolved variables, but need to use underscore _ instead of dots in the variable name.

For example, a variable named Settings.Port should be used as Settings_Port in the template.