Update timezone data to 2016a

Update timezone data to 2016a

  Changes affecting future time stamps

    America/Cayman will not observe daylight saving this year after all.
    Revert our guess that it would.  (Thanks to Matt Johnson.)

    Asia/Chita switches from +0800 to +0900 on 2016-03-27 at 02:00.
    (Thanks to Alexander Krivenyshev.)

    Asia/Tehran now has DST predictions for the year 2038 and later,
    to be March 21 00:00 to September 21 00:00.  This is likely better
    than predicting no DST, albeit off by a day every now and then.

  Changes affecting past and future time stamps

    America/Metlakatla switched from PST all year to AKST/AKDT on
    2015-11-01 at 02:00.  (Thanks to Steffen Thorsen.)

    America/Santa_Isabel has been removed, and replaced with a
    backward compatibility link to America/Tijuana.  Its contents were
    apparently based on a misreading of Mexican legislation.

  Changes affecting past time stamps

    Asia/Karachi's two transition times in 2002 were off by a minute.
    (Thanks to Matt Johnson.)

Bug: 26833368
Change-Id: I5af1d69f8ca767369f1cbc4aa863280b960777e0