Name Changes to Align with V0.3

[terencechain]

This is part of #1542

Updated the following names:

• penalized -> slashed
• exit -> voluntary exit
• initial, startup -> genesis
• SEED_LOOKAHEAD -> MIN_SEED_LOOKAHED
• ENTRY_EXIT_DELAY -> ACTIVATION_EXIT_DELAY
• INCLUDER_REWARD_QUOTIENT -> ATTESTATION_INCLUSION_REWARD_QUOTIENT
• latest_index_roots -> latest_active_index_roots
• current_epoch_start_shard -> current_shuffling_start_shard, current_shuffling_epoch, current_shuffling_seed
• MIN_VALIDATOR_WITHDRAWAL_EPOCHS -> MIN_VALIDATOR_WITHDRAWAL_DELAY
• MAX_WITHDRAWALS_PER_EPOCH -> MAX_EXIT_DEQUEUES_PER_EPOCH
• ETH1_DATA_VOTING_PERIOD -> EPOCHS_PER_ETH1_VOTING_PERIOD
• SLOT_DURATION -> SECONDS_PER_SLOT
• EPOCH_LENGTH -> SLOTS_PER_EPOCH

Not Updated yet. Waiting for dicussion:

• ChainStart -> Eth2Genesis
• operations -> transactions

Reference: ethereum/consensus-specs#534

[codecov]

Codecov Report

Merging #1621 into master will increase coverage by 0.05%.
The diff coverage is 87.74%.

@@            Coverage Diff             @@
##           master    #1621      +/-   ##
==========================================
+ Coverage   71.06%   71.12%   +0.05%     
==========================================
  Files          94       94              
  Lines        6628     6614      -14     
==========================================
- Hits         4710     4704       -6     
+ Misses       1505     1504       -1     
+ Partials      413      406       -7

[rauljordan]

Better to get this in soon to not have to resolve conflicts later, thanks for doing this big effort!