[MlMt] dates

[Randy Bush]

a received message written in pdt, gmt-7

the date in the real header is Fri, 31 Jul 2015 12:03:26 -0700
mailmate shows the date as July 31, 2015 at 21:03
the laptop time here in tokyo when it was written was Aug 01 at 04:03

aha!  the last time mailmate was started was some days back in praha or
roma.  so mailmate uses an internal clock, not system, to convert to
local time for the user.  probably not ideal for travelers.

randy