Add the ability to distinguish var files

[yorinasub17]

Describe the solution you'd like
We use var files to pass boilerplate variables, but that gets interpretted as a template and is automatically included in the copy. Is there someway we can input the var files so that it is always ignored from the template rendering?

Describe alternatives you've considered
Current workaround is to explicitly add each var file to skip_files so that it is explicitly skipped.