examples: wiringPiISR usage example

examples/callback.py

@@ -0,0 +1,14 @@
+import wiringpi2
+PIN_TO_SENSE = 23
+
+def gpio_callback():
+    print "GPIO_CALLBACK!"
+
+wiringpi2.wiringPiSetupGpio()
+wiringpi2.pinMode(PIN_TO_SENSE, wiringpi2.GPIO.INPUT)
+wiringpi2.pullUpDnControl(PIN_TO_SENSE, wiringpi2.GPIO.PUD_UP)
+
+wiringpi2.wiringPiISR(PIN_TO_SENSE, wiringpi2.GPIO.INT_EDGE_BOTH, gpio_callback)
+
+while True:
+    wiringpi2.delay(2000)