Backports into beta (#2512)

* RocksDB version bump

* Preserve cache on reverting the snapshot (#2488)

* Preserve cache on reverting the snapshot

* Renamed merge_with into replace_with

* Renamed and documented snapshotting methods

* Track dirty accounts in the state (#2461)

* State to track dirty accounts

* Removed clone_for_snapshot

* Renaming stuff

* Documentation and other minor fixes

* Replaced MaybeAccount with Option

* Adjustable stack size for EVM (#2483)

* stack size for io workers & evm threshold

* rust way to remember stack size

* right value

* 24kb size

* some stack reduction

* Fixed overflow panic in handshake_panic (#2495)