Add zcash support

src/js/bitcoinjs-extensions.js

@@ -1199,3 +1199,14 @@ bitcoinjs.bitcoin.networks.zcoin = {
   scriptHash: 0x07,
   wif: 0xd2,
 };
+
+bitcoinjs.bitcoin.networks.zcash = {
+  messagePrefix: '\x18Zcash Signed Message:\n',
+  bip32: {
+    public: 0x0488B21E,
+    private: 0x0488ADE4,
+  },
+  pubKeyHash: 0x1CB8,
+  scriptHash: 0x1CBD,
+  wif: 0x80,
+};