* Move blockchain::rocksdb into a separate crate

* Add license and description for blockchain-rocksdb

* Add support for crosslink tests

* Add support for registry updates test

* Refresh support for deposit operation

* Add support for attestation test

* Add support for attester slashing test

* Add BlockHeader tests

* Add support for proposer slashing tests

* Add support for transfer tests

* Add support for blocks and slots sanity test

* Add scripts to run state tests

* Fix script

* Fix test path change

* Refactor duplicate into code

* Upgrade lmd-ghost to newer blockchain version

* Implement ShasperBackend

* Upgrade to blockchain 0.7

* Implement commit and chain query interface for rocksdb

* RocksDB backend creation logic

* Add rocksdb invocation from commandline

* Update README and upgrade blockchain client to newer version

* Remove unfinished pruning lmd-ghost strategy

* Move substrate-specific crates to subfolder substrate

* Fix cargo lock

* Fix CI

* Check in runtime wasm file

* Expose proposer index and pubkey to executor

* Use importer even for self-built blocks

* Remove unused imports

* New block builder routine

* Switch to real bls implementation and properly sign all data structures

* Fix compile warning

* Add conditional compile for serde(skip)

* fix: ancestorQuery should never return None

* fix: lmd-ghost error types unification

* Make lmd-ghost properly set head

* Implement JustifiableExecutor for beacon block struct

* Replace BestDepthImporter with ArchiveGhostImporter

* Create archive lmd-ghost impl for simplicity

* Add blockchain executable directly built on top of libp2p

* Fix tests

* [WIP] Update all config and struct definitions

* [WIP] Utils function spec update I

* [WIP] Utils functions spec update II

* [WIP] Re-init beacon

Cherry-pick back old code rather than modifying it is easier to do -- as there are many changes.

* [WIP] Cherry-pick back all types

* [WIP] Cherry pick back all helpers

* [WIP] Cherry-pick back validator status helpers

* [WIP] Migrate back per epoch helpers

* [WIP] Cherry-pick justification and finalization

* [WIP] Redo crosslink and rewards

* [WIP] Cherry-pick back all per epoch operations

* [WIP]

* [WIP] Port back all operations

* Add state root verification

* [WIP] Fix warnings

* Finish fixing all warnings

* Add function to execute block

* Add back small config

* Add new test repo

* Update yamltests for the new format and pass those tests

* Check block state root in execute_block

* Add full tests

* Update tests

* Add back block builder

* Fix other crate compile

* Make beacon crate work again in no_std

* beacon: UnsealedBeaconBlock

* Upgrade blockchain to 0.5.1

* Simple interface to blockchain

* Add block builder interface

* All basic ops for hashing using Digest interface

* Add support for digestible in ssz-derive

* Add Digestible interface for beacon crate