Add CashAddr Address Format

Ported from Bitcoin Unlimited, Bitcoin ABC

src/config.cpp

@@ -0,0 +1,16 @@
+// 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.
+
+#include "config.h"
+#include "chainparams.h"
+#include "consensus/consensus.h"
+
+GlobalConfig::GlobalConfig() : useCashAddr(false) {}
+const CChainParams &GlobalConfig::GetChainParams() const { return Params(); }
+static GlobalConfig gConfig;
+
+const Config &GetConfig() { return gConfig; }
+void GlobalConfig::SetCashAddrEncoding(bool c) { useCashAddr = c; }
+bool GlobalConfig::UseCashAddrEncoding() const { return useCashAddr; }
+const CChainParams &DummyConfig::GetChainParams() const { return Params(CBaseChainParams::REGTEST); }