Consolidate CTransaction hex encode/decode into core_io.h, core_{read,write}.cpp

src/core_io.h

@@ -0,0 +1,14 @@
+#ifndef __BITCOIN_CORE_IO_H__
+#define __BITCOIN_CORE_IO_H__
+
+#include <string>
+
+class CTransaction;
+
+// core_read.cpp
+extern bool DecodeHexTx(CTransaction& tx, const std::string& strHexTx);
+
+// core_write.cpp
+extern std::string EncodeHexTx(const CTransaction& tx);
+
+#endif // __BITCOIN_CORE_IO_H__