Update DHT22.py

cleanup an adding DHT11-Type

conecting:
Pin1 to 3.3V
Pin2 to 'Y2' or 'Y9'
NC = Do not connect
Pin4 to GND

Pin1-[2KOhm]-Pin2


-> only one Pin for the DHT-sensor
You save 3 Pin !

TODO: rename DHT22.phy to DHT.py ?

thank-you