RFR: 8246129: ZIP entries created for DOS epoch include local timezone metadata

[Claes Redestad]

Hi,

this patch addresses a corner case where extra time stamp information
is added when using start of the DOS time epoch (1980-01-01 00:00:00)
as a dummy timestamp for entries

Bug:    https://bugs.openjdk.java.net/browse/JDK-8246129
Webrev: http://cr.openjdk.java.net/~redestad/8246129/open.00/

Testing: tier1-2

Thanks!

/Claes