Merge pull request adafruit#28 from bahamas10/patch-1

dht script should exit non-zero if reading failed

Author: tdicola

examples/AdafruitDHT.py

@@ -48,3 +48,4 @@
 	print 'Temp={0:0.1f}*C  Humidity={1:0.1f}%'.format(temperature, humidity)
 else:
 	print 'Failed to get reading. Try again!'
+	sys.exit(1)