Add CashAddr Address Format

Ported from Bitcoin Unlimited, Bitcoin ABC

src/cashaddrenc.h

@@ -0,0 +1,33 @@
+// Copyright (c) 2017 The Bitcoin developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+#ifndef BITCOIN_CASHADDRENC_H
+#define BITCOIN_CASHADDRENC_H
+
+#include "script/standard.h"
+
+#include <string>
+#include <vector>
+
+class CChainParams;
+
+enum CashAddrType : uint8_t
+{
+    PUBKEY_TYPE = 0,
+    SCRIPT_TYPE = 1
+};
+
+std::string EncodeCashAddr(const CTxDestination &, const CChainParams &);
+
+struct CashAddrContent
+{
+    CashAddrType type;
+    std::vector<uint8_t> hash;
+};
+
+CTxDestination DecodeCashAddr(const std::string &addr, const CChainParams &params);
+CashAddrContent DecodeCashAddrContent(const std::string &addr, const CChainParams &params);
+CTxDestination DecodeCashAddrDestination(const CashAddrContent &content);
+
+std::vector<uint8_t> PackCashAddrContent(const CashAddrContent &content);
+#endif