DataValidator issues with correct fields

In dataValidator_v1.1.jar

`Population purpose is not in correct format: yes`

Although described as such: https://docs.google.com/spreadsheets/d/18BsU3wdWvpE5emqy7TUBUO5Si-m-X368D1b-E4s_n5g/edit#gid=205398708 and present in current mitodb dataset - datatype string - could also be boolean