added variable sizes 4 nano

snipplets/code/Arduino/variables_sizes.ino

@@ -52,3 +52,16 @@ void setup() {
 void loop() {
   //
 }
+
+/**
+ * Arduino Nano
+ *
+ * int bytes size:            2
+ * unsigned int bytes size:   2
+ * signed int bytes size:     2
+ * unsigned long bytes size:  4
+ * float bytes size:          4
+ * double bytes size:         4
+ * char bytes size:           1
+ * char * bytes size:         2
+ */