Added documentation and changed the Endpoints to match Rest conventions, added query attributes for use-case, tables  and layers. Also modified a bit of repository and calculate similarity code to work with the refactoring/adding of use-cases and tables

type_label is in {'high', 'medium', 'low', 'noise'}

Cluster sizes might get too large, so they will still be stored on disk.

bugifx: an exception was thrown when an int is passed as a UniqueID field -> now converted to string