[tz] leap seconds (srsly)

[Zefram]

In a couple of months, a decision is going to be made about possibly
ceasing leap seconds in UTC.  If that happens, the tz database is going
to be thrown into a world of hurt, as "UTC = GMT" gradually ceases to
be a viable approximation.  Here are the slides from a talk presented a
couple of months ago that provides a useful primer on how the decision
would interact with civil and legal time:

http://www.cacr.caltech.edu/futureofutc/program/presentations/AAS_11-662_Seago.ppt.pdf

All the presentations from the conference where that was presented,
discussing mary aspects of the decision, can be found here:

http://www.cacr.caltech.edu/futureofutc/program/

(Information forwarded from the leapsecs mailing list.)

-zefram