django-cloudinary-storage does not anticipate Windows paths

If a document is named using Windows styled path, the _save method causes problems.

def _save(self, name, content):
    # name is path\to\some\image\image.jpg on Windows machine
    name = self._prepend_prefix(name)
    # name becomes media/path\to\some\image\image.jpg if `settings.MEDIA_URL` is /media/
    ...

At the end, the resulting filename on cloudinary is something like media/\path\to\some\image\image_asdfghjk.jpg/ causing cloudinary to complain.

I think it will be nice if django-cloudinary-storage also works well on Windows. I can supply a fix which makes sure the name variable in _save is in unix style.

[tundebabzy]

Here are snapshots of the error.

By default, zinnia uploads to a directory named ‘uploads’ concatenated with the year, month and day the image was saved hence in this particular case - 'uploads\zinnia\2017\01\11'.

Let me know if you need any more information.

[klis87]

Thank you for your pull request. I added 1 comment to it, please review it, thanks in advance.