fixed date (not accepted date in past) and added test for is_date (to check if date is real it can be in the past)
fixed date in is_valid_date() to accept no date from the past and added new method is_date (validates any date including from the past)
added two new methods -> check_for_event() and clear_old_messages() !  FIXED validation in delete_message() git add User.py
fixed dates
nothing new