Add a define in both the source and Makefile for enabling logging of z80 instruction address/cycle counts. Fix Z80 in/out instructions to eliminate assumptions about which registers are stored in native regs. Fix read_16 to not corrupt the low byte when the read has to call into a C function.

--- a/z80_to_x86.h	Mon May 25 17:08:56 2015 -0700
+++ b/z80_to_x86.h	Mon May 25 18:56:22 2015 -0700
@@ -9,7 +9,11 @@
 #include "backend.h"
 
 #define ZNUM_MEM_AREAS 4
+#ifdef Z80_LOG_ADDRESS
+#define ZMAX_NATIVE_SIZE 255
+#else
 #define ZMAX_NATIVE_SIZE 128
+#endif
 
 enum {
 	ZF_C = 0,