Rename folders as per suggestion from Rajat

ch-02/blink.py

@@ -0,0 +1,12 @@
+import time
+import board
+import digitalio
+
+led = digitalio.DigitalInOut(board.LED)
+led.direction = digitalio.Direction.OUTPUT
+
+while True:
+    led.value = True
+    time.sleep(0.5)
+    led.value = False
+    time.sleep(0.5)

ch-02/helloworld.py

@@ -0,0 +1 @@
+print("Hello, world!")

ch-02/light_led.py

@@ -0,0 +1,6 @@
+import board
+import digitalio
+
+led = digitalio.DigitalInOut(board.LED)
+led.direction = digitalio.Direction.OUTPUT
+led.value = True