Split the CUDADriver recipe into a download and a munki part.

Split the CUDADriver recipe into a download and a Munki part. That way, I can use it with the [Importer](https://github.com/mkuron/autopkg-recipes/blob/master/MunkiServerImporter.py) I wrote for [MunkiServer](https://github.com/jnraine/munkiserver).