Remove trailing space.
Update record serializer implementation into dlist writer.
Export ToSql writer building interfaces.
Rename internal definition.
Update haddock.
Add empty printer. Export ToSqlM.
Fix persistable instance templates for nested case. Fix local names.
Fix persistable width template for nested case.
Add nested record example.
Directory derive FromSql and ToSql from PersistableValue.
Simplify dependencies.
Remove old singleton wrap module.
Reduce export list.
Remove old singleton wrap module.
Reduce dependency to Persistable.
Reduce dependency to Persistable.
Remove Persistable class.
Reduce dependencies to PersistableRecord.