Clean up scripts and add postinstall for installing via git
Clean up scripts and add postinstall for installing via git

BitGo/bitcoinjs-lib,junderw/bitcoinjs-lib,visvirial/bitcoinjs-lib,BitGo/bitcoinjs-lib,junderw/bitcoinjs-lib,bitcoinjs/bitcoinjs-lib,bitcoinjs/bitcoinjs-lib,visvirial/bitcoinjs-lib