Changed "zero" device timing for reliability.
Changed "zero" device timing for reliability.

Zero pulse time was previously 26µs and has been increased to 27µs. Issue was reported by a user working with an AM2032, which uses the same timing as the DHT22. Maximum pulse time is 30µs, with 26 to 28 µs shown on the datasheet timing diagrams.
electricimp/reference,AG6GR/reference,AG6GR/reference,electricimp/reference