Start of project

If one param is more like to be ```nil```/not included, convention is for it to be the last param with an option value. I.e.
```
def create_client_file(folder, client_file = nil)
```
That way, if you don't have a client file, instead of ```create_client_file(nil,"successful_import_undos")```, you can just do ```create_client_file("successful_import_undos")```

Also, since there really is no overlap, this should probably be two separate methods, one if you provide a file and one if you don't. Not that big of a deal though.