Using a Keep Module results in extra data in hospital/practitionerInfo files

[dehall]

(originally identified in #1377 )

When using a Keep Module that filters a lot of patients out, the hospitalInfo and practitionerInfo files still contain info that was associated only to patients that were generated but not exported. (This may also be the case when using generate.only_dead_patients=true or generate.only_dead_patients=true ) If the Keep Module is looking for something especially rare the files can get very large.

There should be a way to filter the hospital and practitioner Info files to only include the necessary records for the patients that were actually exported