使用sha函数实现哈希查找，希望对于初学P2P的人有一定帮助-use Hash Function find hope for the peer-to-peer learning will definitely help

SHA-3 / Keccak / Shake哈希算法的Javascr ipt实现，支持UTF-8。(A simple SHA-3 / Keccak / Shake hash function for Javascr ipt supports UTF-8 encoding.)