Convert recipe examples to includes

Makes it much easier to test things - no copying'n'pasting just run the
examples straight from the dir (after wiring stuff up)

docs/examples/led_1.py

@@ -0,0 +1,10 @@
+from gpiozero import LED
+from time import sleep
+
+red = LED(17)
+
+while True:
+    red.on()
+    sleep(1)
+    red.off()
+    sleep(1)