quality of life improvement: kea-admin db-version fails on empty db
kea-admin db-version prints the following error:
# kea-admin db-version mysql mysql: [Warning] Using a password on the command line interface can be insecure. ERROR 1146 (42S02) at line 1: Table 'keatest.schema_version' doesn't exist
when run on an empty DB (without any schema).
Instead, it should catch the fact that schema_version does not exist and should point user to kea-admin db-init command.
This is a quality of life improvement, so it's not terribly important.