Mainnet:
```
447M accounts.0-544.l
45M accounts.0-544.li
133M code.0-544.l
14M code.0-544.li
2.0G storage.0-544.l
197M storage.0-544.li
```
Decided no to use Roaring - because it can only keep full bitmap in RAM
(no way to stream into file). But it's more compact 2Gb -> 1.4Gb. Maybe
can shard large bitmap - or do other trick (storage has 1B keys -
sharding probably is cheap). Maybe in the future.
