add support of remote storage

[badziyoussef]

Actually, the package is not compatible with django-storages, which is a valuable feature, as django can run in production in a scallable environment, actually with django-storages it raise (see screenshot bellow)

[badziyoussef]

@pfouque can we move forward with this PR? the bug is a real blocker when using Google Oauth2

[pfouque]

Hi @badziyoussef,
Firstly, It would be easier to merge two separate PR, with distinct purposes.

Additionally, merging doesn't necessarily mean a new release will be published soon.
So I'd recommend you, especially if it's urgent, to run your project using your own fork in the meantime (Multiple solutions exist to do so, with or without publishing to pypi).