Strange get_original_storage_full_path logic

[pahaz]

https://github.com/chibisov/django-proxy-storage/blob/e387cab9190d0a788cc15a87b2cc242919cb5bde/proxy_storage/storages/base.py#L61-L66

path -- Returns a local filesystem path where the file can be retrieved using Python's built-in open() function.

This is not a good solution for meta_backend path.

[pahaz]

this issue related with #7