Smugmug transfer extension

[seehamrun]

Whats left:

• Move importer side to use the scribe API for signing post requests
• Fully test export.
• The export only gets public data - this is likely an issue with the auth data generator and needs debugging
• Can't get smugmug -> flickr working due to unrecongized file type, and smugmug -> google photos renders a black image instead of the actual image (not clear if the issue is on the exporter or the importer side, since for public images, the photo resources look correct.)

[seehamrun]

Still can't get smugmug upload to work, going to put on the backlog for now and disable from the demo-server

Updated list of what's left / errors I'm running into:

• Importer side uses scribe API and album creation works, but image upload doesn't and just has an "unauthorized" error (and no details as to why).
  • I thought this might be because we mark the album as private and then try to upload photos, but making albums public didn't fix things either.
  • Docs on uploading can be found here: https://api.smugmug.com/api/v2/doc/reference/upload.html and https://api.smugmug.com/services/api/?method=upload
• AuthDataGenerator now has access to private data and correct permissions, but it still doesnt look like we get "hidden" images within albums (we do get private albums though, haven't tested private albums with content..).
• public images uploaded to other services (Google photos) are still corrupt (black empty image), even though I am able to get to the content fetchable url and download successfully - This might be the same reason why Flickr is rejecting the photo with "unrecognized file type".