* Aristo: Code cosmetics, e.g. update some CamelCase names
* CoreDb+Aristo: Provide oldest known state root implied
details:
The Aristo journal allows to recover earlier but not all state roots.
* Aristo: Fix journal backward index operator, e.g. `[^1]`
* Aristo: Fix journal updater
why:
The `fifosStore()` store function slightly misinterpreted the update
instructions when translation is to database `put()` functions. The
effect was that the journal was ever growing due to stale entries which
were never deleted.
* CoreDb+Aristo: Provide utils for purging stale data from the KVT
details:
See earlier patch, not all state roots are available. This patch
provides a mapping from some state root to a block number and allows to
remove all KVT data related to a particular block number
* Aristo+Kvt: Implement a clean up schedule for expired data in KVT
why:
For a single state ledger like `Aristo`, there is only a limited
backlog of states. So KVT data (i.e. headers etc.) are cleaned up
regularly
* Fix copyright year
Jordan Hrycaj