Review data provider arguments.

[emanlove]

There are a few keywords which from the docs display arguments as *args, **kwargs +. Beside being unclear on what these arguments are, I am not sure the current implementation can properly translate data types (if any are required). So we should review arguments of the data providers and see if we can better support passing arguments from robot to faker on data providers.

+ Footnote: The fact that arguments are unnamed or generic itself might only be solved within Faker. There is some options to correct that within the FakerLibrary side. But the maintenance and change cost may be too high for that.