centralized printf formats and improved log_displayer performance
Before, log_displayer copied each message into the same structure that
gets put into queues etc so that it could be printed with the same
function. Now, it prints it directly, but using the same formats.
diff --git a/aos/common/macros.h b/aos/common/macros.h
index 2018b36..ba23fe4 100644
--- a/aos/common/macros.h
+++ b/aos/common/macros.h
@@ -22,4 +22,7 @@
#define UNUSED_VARIABLE
#endif
+#define STRINGIFY(x) TO_STRING(x)
+#define TO_STRING(x) #x
+
#endif // _AOS_COMMON_MACROS_H_