* begin 0.5.0 spec update: parent_root -> previous_block_root, BeaconState.justified_epoch -> BeaconState.current_justified_epoch, DOMAIN_PROPOSAL -> DOMAIN_BEACON_BLOCK, temporarily rename BeaconBlockHeader to BeaconBlockHeaderRLP to allow for gradual re-merging without disrupting RLP; mark a few unchanged functions and data types, implement get_temporary_block_header/get_empty_block/should_update_validator_registry/processBlockHeader/cacheState; update a few others
* a dozen or so more trivial mostly comment changes, finding more unchanged parts of 0.5.0
* several more trivial changes; goal is to reduce noise around the upcoming substantial changes (epoch processing, etc)
* remove some redundant state updates
* when attesting late, use correct state / head
* don't send out obsolete attestations
* don't propose obsolete blocks
* remove some more resundant state updates :)
* simplify block logging (experimental)
* document fork choice division
* fix some Slot / Epoch conversion warnings
* fix state db lookup typo
* fix randao reveal slot when proposing blocks
* only store blocks that can be applied to a state
* store state at every epoch boundary (yes, needs pruning!)
* split out state advancement function when there's no block
* default state sim to 0.9 attestation ratio
* processEpoch 5x faster, total 2x faster, with 16k validators
* don't recompute active_validator_indices as much
* remove duplicate process_ejections function
* prevent balance underflow, per spec implementation note
* verify that permutation shuffing works: add YAML dependency to be used for ingesting test cases; switch from blake2 to keccak256 to match EF test cases; remove inefficient naive-spec-version of shuffling algorithm now that protolambda's can be tested directly
* Complete scan through v0.3.0 spec; remaining known discreptancy is in bls_verify_multiple
* switch remaining slot-misuses of get_active_validator_indices to epochs
* spec workaround
* finish first 0.3.0 pass by getting slow, naive version of bls_verify_multiple running
* implement in-memory block graph
* store tail block in database
* resolve unknown parents by syncing them from peers
* introduce concept of resolved blocks and attestations - those that
follow minimal protocol rules
* update state head lazily
* log more stuff
* shortHash -> shortLog
* start 9/10 beacon nodes by default, last can be started manually
* see also #134
* fix start.sh epoch length
* convert some asserts to doAsserts to keep them in release mode builds; rename get_initial_beacon_state to get_genesis_beacon_state to track spec; switch target spec version to 0.3.0; switch references to penalize_validator to slash_validator/slashValidator to track spec; make some function returns safer by omitting 'return'
* 2x shuffling speedup by hoisting pivot calculations per https://github.com/protolambda/eth2-shuffle
* fix initial attestation pool on reordered attestations
* simplify db layer api
* load head block from database on startup, then load state
* significantly changes database format
* move subscriptions to separate proc's
* implement block replay from historical state
* avoid rescheduling epoch actions on block receipt (why?)
* make sure genesis block is created and used
* relax initial state sim parameters a bit
* switch to v0.2.0 shuffling scheme
* fix some >80 char lines; add get_total_balance helper function (used in epoch processing, etc); note intended removal of repeat_hash and users thereof; add some int_to_bytes and bytes_to_int helpers; more underflow comments; add Gwei type; adjust generate_seed to include additional entropy source; note egregious inefficiencies
* minor code cleanup
* move some general helper functions to helpers.nim and clarify little-endian comments
* s/slot_included/inclusion_slot/; s/participation_bitfield/aggregation_bitfield/; rearrange some type definitions to match spec order
* a couple more Eth1Data-related spec syncs
Dustin Brody
Jacek Sieka
Zahary Karadjov
Yuriy Glukhov
Jacek Sieka
Mamy Ratsimbazafy