sdk: Change night/day mode transition behavior

* Update 2x a minute rather than 1x a minute as a result of dropping
  TWILIGHT_ADJUSTMENT_TIME from 1hr to 30min in an earlier change
* Use an AccelerateDecelerateInterpolator for transitioning from day
  to night mode and back to make the transition smoother for the user
* Update copyright while we're at it

Change-Id: I438f265c6cd9a2487b75744beccaf2bbac21b36e