qiita_user and study_person should be related

[adamrp]

trafficstars

Currently, there are some columns replicated between qiita_user and study_person (name, affiliation, phone, address). It would be better to remove those columns from qiita_user, but then when a new user is created, add a corresponding entry into study_person, and add a foreign key from qiita_user into study_person)