* Update some docu & messages
* Remove cruft from the ledger modules
* Must not overwrite genesis data on an initialised database
why:
This will overwrite the global state of the Aristo single state DB.
Otherwise resuming at the last synced state becomes impossible.
* Provide latest block number from journal
why:
This relates the global state of the DB directly to the corresponding
block number.
* Implemented unit test providing DB pre-load and resume
Jordan Hrycaj