Disable persistence function to rewrite/modify or delete.
Save samples, but doesn't return ids.
Implement Bulk insert  and variants.
Bulk load simple object work.
Fix bulk_insert_multi to save id.
Add dirty key
Bulk update works for attributes.
Add suppor to save parents and children
Refactor parents and children methods
Computes parents from attributes
Bulk load in progress
bulk load seems to work.
Sync version number to 2.5-pre
Create and load empty plate works.
Manage loaded resource.
Create and read plate with sample works
Fix update
Refactor persistor slice using bulk load.
new_from_attribute uses block if provided.
Plate specs pass.