Minor improvements

Completely untested, because I don't know how to test this project manually, and there are no automated tests. (Why are there no automated tests?)
`resource_id ` is an integer, while `self.recommenations` is a list of dictionary. Thus `idx = self.recommenations.index(resource_id)` is incorrect. The function `get_entry_index ` tries to find the resource element index `idx` such that `self.recommenations[idx]['id'] = resource_id`