update mainnet checkpoints to post-halving block 540,000
update mainnet checkpoints to post-halving block 540,000
novaexchange/EAC,novaexchange/EAC,earthcoinproject/earthcoin,novaexchange/EAC,novaexchange/EAC,earthcoinproject/earthcoin,earthcoinproject/earthcoin,earthcoinproject/earthcoin,novaexchange/EAC,earthcoinproject/earthcoin