create sample project
sample: configure filecabinet with local filesystem
replace sorl-thumbnails for easy_thumbnails

Don't use the easy_thumbnails database at all, just the image resize logic.

Other minor changes:

 - on the upload pipeline, delete() step will no longer receives
   the file object, it receives the filedict

 - remove the parallelization on image generation, for now

 - syntax for FILECABINET_IMAGE_VERSIONS setting has changed to
   easy_thumbnails format