Bugfixes
- Fixed hardcoded storage backend of the "FirmwareImage.file" field.
FirmwareImage.filewas configured to usePrivateFileSystemStorage, which made it impossible to use other private storage backends. The "OPENWISP_FIRMWARE_PRIVATE_STORAGE_INSTANCE" setting is added to make theFirmwareImage.filestorage configurable. - Fixed inconsistent URL keyword argument in "serve_private_file" URL pattern. This broke the reverse proxy feature of django-private-storage.