Add support to multicall

[leafyoung]

0x5BA1e12693Dc8F9c48aAD8770482f4739bEeD696

Reference:
https://github.com/eth-brownie/brownie/blob/837db7a0d4d09412d18b1a8e9ce12af2262a346b/brownie/network/multicall.py

[leafyoung]

https://github.com/kkristof200/py_web3_multicall/tree/master/web3_multicall/_utils