Add tiny example of no stdio support.

example/ex-no-stdio.c

@@ -0,0 +1,16 @@
+/*
+ * Micro example to test if M*LIB supports not using stdio.h
+ */
+#define M_USE_STDIO 0
+#define M_RAISE_FATAL(...) abort()
+#include "m-array.h"
+
+ARRAY_DEF(arr, int)
+
+int main(void) {
+    arr_t a;
+    arr_init(a);
+    arr_push_back(a, 4);
+    arr_clear(a);
+    return 0;
+}