datastore fields names have inconsistent use of '_' vs '-'

[unreasonableman]

some names are of the form 'field-name' and some use 'field_name'. This is not just a stylistic problem because there are fields like 'agency_id' and 'agency-id' in diifferent entity kinds. These fields processed in common code, which means we need to check for both flavors there.

The main issue besides just changing the code to use consistent naming is to change field names for DB entries, which for some entities is in the millions. We need to find out if there is support for bulk attribute name changes.