Code CleanUp (Changes from v1-audit)

[Yashk767]

• 1. Refactors (Refactors #864)

• change getDelayedState to getBufferedState

• remove uint64 from block time

• change int to uint in constants

• getSalt cleanup (typos)

• Change handleRevealState to checkForLastCommitted

• CalculateBlockNumberAtEpochBeginning rename to EstimateBlockNumberAtEpochBeginning

• GetStatesAllowed rename to GetFormattedStateNames and remove the comma logic

• ClaimStakeReward rename to ClaimStakerReward

• 2. tx hash logging needs to be more consistent throughout (tx hash logging needs to be more consistent throughout #846)

• 3. remove redundant uint typecast , In GetEpoch(), uint64 needs to be removed (In GetEpoch(), uint64 needs to be removed #844)

• 4. Update coinContract to erc20contract (Rename coin contract to erc20contract #842)

• 5. Move standard logger json formatter to common in logger.go/initialise logger (Move standard logger json formatter to common in logger.go/initialise logger #833)