Project/Util/gitweb: avoid bizarre Time::Local year interpretation

Project/Util/gitweb: avoid bizarre Time::Local year interpretation

Although the Time::Local timegm and timelocal functions appear
to be the inverse of the built-in gmtime and localtime functions,
they are not.

When Time::Local functions are passed a year value in the range
0..99 inclusive (as might be returned from the built-in gmtime
and localtime functions), it will be misinterpreted.

Instead, always pass the actual year value to the Time::Local
functions to avoid misinterpretation.

Signed-off-by: Kyle J. McKay <mackyle@gmail.com>