bubble sort + fixed issue when writing to reference in ram.py

src/Makefile

@@ -1,5 +1,13 @@
 LDFLAGS="-L/usr/local/opt/flex/lib"
 
+
+bubble_sort: ram
+	./ram < bubble_sort.asm
+	echo "### machine.py ###"
+	cat machine.py
+	echo "### execution ###"
+	python machine.py
+
 a_pow_b: ram
 	./ram < a_pow_b.asm
 	echo "### machine.py ###"