Since we cannot depend on InnoDB features across all mysql
installations, we are instead using this new column to track
metadata changes for a particular package base.
This will allow us to fetch less data when producing metadata
archives for end-users, and it does not depend on installation
details aside from the schema/migrations being applied.
New columns:
- `PackageBase`.`MetaModifiedTS`
Signed-off-by: Kevin Morris <kevr@0cost.org>