make sure our FK columns are not-null
fix failing uploads. regression introduced in 6c161801215051cc4ebe9ca720b05c15d5970f56 #618
collection may not have a creator
collection may not have a creator
pg constraint means collection_id must be set on initial INSERT
satisfy new not-null pg constraints in factorygirl constructs
add org.entity method so we can treat an Org like a User
standarize iso datetime display for activeadmin