#1: added another test (timeseries not existing); tried to have more user-friendly error messages; still struggling why I get doubled quotation marks now

#1: pytest for uploading data with no_autoflush now working; added timeshift_from_utc to data insertion; added error message if trying to insert duplicates

#1: pytest for data established; renamed date_time to datetime; needed 'no_autoflush' in timeseries queries