Showcase scenario

[qnikst]

Document (update documentation) for the cardano-ledger, ledger-state:performance benchmarks, documentation should include the following:

1. how to download the state (this documentation exists and we may leave it as it's today)
2. how to convert utxo.hex to utxo.scls and get some info about the file
3. how to import utxo.scls into the database and run benchmarks

Ideally we want to put that onto our blog/site about the project