Split up source and added basic support for different targets.

targets/_any/include/stdio.h

@@ -0,0 +1,19 @@
+
+#pragma once
+
+#if !defined(BAD_APPLE_OS_STDIO_H_INCLUDED)
+#define BAD_APPLE_OS_STDIO_H_INCLUDED
+
+#include <stdarg.h>
+#include "./detail/common.h"
+
+BA_EXTERN_C_BEGIN
+
+int putchar(int chr) BA_CXX_NOEXCEPT;
+int puts(const char* str) BA_CXX_NOEXCEPT;
+int printf(const char* format, ...) BA_CXX_NOEXCEPT;
+int vprintf(const char* format, va_list vlist) BA_CXX_NOEXCEPT;
+
+BA_EXTERN_C_END
+
+#endif // !defined(BAD_APPLE_OS_STDIO_H_INCLUDED)