Feature #1605

Updated by Alexander Watzinger over 2 years ago

* Replaced forms as parameters for model with data dictionaries for more generic access  
 * Split classes from model into separate files 
 * Merged source translation insert/update/delete into generic entity functions 
 * Reversed type.root so that root[O] is now the root type and root[-1] the super type 
 * Renamed nodes to types 
 * Renamed view entity_view to view 
 * Merged different spellings of writable/writeable to writable 
 * Removed siblings pager template 
 * Refactor API tests 
 * Mypy checks 
 * Pylint checks