Test coverage unit tests

See merge request NCER-PD/scheduling-system!100

separate patient data from study data

Closes #181

See merge request NCER-PD/scheduling-system!99

address, city, country, data_born, default_written_communication_language, email, first_name, languages, last_name, phone_number, phone_number_2, phone_number_3, postal_code removed from study_subject (all this information is stored in subject)

the code is fixed so unit test passes