Handle person_dob.nil? case.  #3267
Also removes some stale code from the spec.
Fixed data export id for PartVerif #3267
The data export id changed in the instrument but was not changed in the ODE.
Rewording test case for c_dob #3267
Based on David's comment.
Merge pull request #36 from NUBIC/task_3267

Bug 3267 - Date of Birth is not being saved on Child record