* initial fork-choice refactor
* Add fork_choice test for "no votes"
* Initial test with voting: fix handling of unknown validators and parent blocks
* Fix tiebreak of votes
* Cleanup debugging traces
* Complexify the vote test
* fakeHash use the bigEndian repr of number + fix tiebreak for good
* Stash changes: found critical bug in nimcrypto `==` and var openarray
* Passing fork choice tests with varying votes
* Add FFG fork choice scenario + fork choice to the test suite
* Not sure why lmdb / rocksdb reappeared in rebase
* Add sanity checks to .nimble file + integrate fork choice tests to the test DB and test timing
* Cleanup debugging echos
* nimcrypto fix https://github.com/status-im/nim-beacon-chain/pull/864 as been merged, remove TODO comment
* Turn fork choice exception-free
* Cleanup "result" to ensure early return is properly used
* Add a comment on private/public error code vs Result
* result -> results following https://github.com/status-im/nim-beacon-chain/pull/866
* Address comments:
- raises: [Defect] doesn't work -> TODO
- process_attestation cannot fail
- try/except as expression pending Nim v1.2.0
- cleanup TODOs
* re-enable all sanity checks
* tag no raise for process_attestation
* use raises defect everywhere in fork choice and fix process_attestation test