Adding father_alive field to importer and fixtures

Jira story: https://osraav.atlassian.net/browse/OSRA-221

Jira tasks:
OSRA-224#Code-Review
OSRA-226#Code-Review

- Added father_alive to pending_orphan model
- Added father_alive column to importer yaml settings
- Updated fixture files to new format
- Temporarily disabled father_date_of_death validation
Seeing this makes me wonder how we can avoid the future pains of reformatting the entire importer config every time a change needs to be made. And as a more immediate concern: should there be a validation on the settings to ensure at least that the sequence of column names is not broken?