emrtd: Push initial code

Can only read EF_CardAccess currently, but has abstractions for
selecting AIDs and reading files, which was the Hard Part so far

Based heavily on mrpkey by rfidiot

client/src/cmdhfemrtd.h

@@ -0,0 +1,19 @@
+//-----------------------------------------------------------------------------
+// Copyright (C) 2020 A. Ozkal
+//
+// This code is licensed to you under the terms of the GNU GPL, version 2 or,
+// at your option, any later version. See the LICENSE.txt file for the text of
+// the license.
+//-----------------------------------------------------------------------------
+// High frequency Electronic Machine Readable Travel Document commands
+//-----------------------------------------------------------------------------
+
+#ifndef CMDHFEMRTD_H__
+#define CMDHFEMRTD_H__
+
+#include "common.h"
+
+int CmdHFeMRTD(const char *Cmd);
+
+int infoHF_EMRTD(void);
+#endif