The remaining testing / functionalities work:
  - check if creation of images for experiment channels work 
  - locate and test all api methods for fetching registered images
  - test adding thumbnails to already existing image datasets
  - test removing image datasets, removing some thumbnails, check that other images are still visible. Check for orphan entries in imaging_db

The remaining work in imaging_db:
  - refactor images into acquired images. This is necessary or we will have to do some gimnastics to keep database clean(orphan objects) and consistent
  - refactor full path to the acuired images (get rid of path prefix in the zoom_level)